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The ANT+ Bike Speed/Cadence Sensor: Everything you ever wanted to know

After the popular ‘everything you ever wanted to know’ post I did back this winter on the footpod, I decided it was time to continue the series with the Speed/Cadence sensor.  Thankfully, the speed/cadence sensor is actually a bit less mysterious than the footpod, primarily because it’s a very mathematically simple device (unlike the footpod which calculates distance based on a number of calibrated factors).

So let’s start out – what exactly is it?

IMG_9396

Well, there’s actually three different ANT+ sensor types related to this area, which align to the three different official ANT+ sensor device profiles for speed & cadence sensors.  You have:

1) Speed Only Sensor: This unit uses a wheel sensor and magnet that’s mounted on the frame with a magnet on the rear wheel to measure speed and distance.  Because the wheel circumference is known (manually entered, or calibrated via GPS), each time the magnet passes the sensor a simple mathematical calculation can be made to determine overall speed and distance.

2) Cadence Only Sensor: This unit uses a cadence sensor on your frame and a magnet on your crank to measure cadence.  The crank is the arm that the pedal connects to (and in turn, your cleat then shoe then foot). Each time your crank arm passes the sensor a single revolution is recorded.

3) Speed/Cadence Combo Sensor: This is by far the most popular type. This unit type sends both speed and cadence information wirelessly to the head unit, and does so usually using a single device (either one piece physically or two small pieces connected via wire)  mounted near the rear wheel.  It’s simply a combination of the first two unit types I noted.

Each of these different devices uses a different ANT+ ‘profile’ type, which means that just because a device supports one profile type, doesn’t mean it’ll support the other types.  The combo sensor type was the oldest, and is the most widely supported.  I know of no ANT+ devices that fail to support it.  Meanwhile, the speed-only and cadence-only sensor types are newer and far less supported.  For example, the Garmin FR305 doesn’t support these newer ANT+ profiles.

What do I mean by ANT+ profiles/device types?  Well, every ANT+ device has a profile, think of it like a ‘classification’.  There are ANT+ Heart Rate Straps (HRM Device Profile), Power Meters (PWR Meter device profile) and others.  There are even new profiles coming for data streams like Skin Surface Temperature and Electric Bikes (LEV).  Each of these is simply a standard identifying a device, as without standards ANT+ as a ecosystem wouldn’t work too well.

Speed/Cadence Sensors:

For most folks, the most common Speed/Cadence sensor is the $35 Garmin GSC-10.  Without question it’s the Microsoft Office of the ANT+ world – almost everyone has it.  This simply has three pieces.  The first is the spoke magnet (seen left), then the cadence magnet (seen right), and finally the electronics pod mounted to your frame that has two magnet sensors capturing both speed (upper moving arm off unit) and cadence (lower right side of unit).

image

But there are others that have created Speed/Cadence combo sensors as well, most with slightly differing designs.  Some of these designs are meant to solve certain bike frame configurations where the GSC-10 doesn’t work well by using a small wire to bridge a separate pieces for the speed and cadence data.  This gives more flexible installation options Ultimately the unit combines the data together though so it shows up at an ANT+ combo sensor.  For example, below is the Wahoo Fitness combo sensor:

IMG_9923

I suppose the above picture probably deserves some explanation (I generally feel any photos with cutting devices probably do).  The Wahoo sensor is in the middle about to get snipped, as I was redoing the cabling to play around the idea of extending the short cable in the middle to accommodate a recumbent bike.  I never did get a bike to test with, though conceptually it’s pretty simple and worked just fine on my desk (albeit in a very non-weatherproofed sorta way):

IMG_9946IMG_9949

Speed Only and Cadence Only Sensors:

Next we have those units that are either speed sensors or cadence sensors…but not both.  These sensors are dedicating to delivering either speed data, or cadence data.  They can’t do both, and can only measure what they are designed for (meaning, you can’t use a speed sensor to measure cadence).  The most common reason people by these sensors over combo sensors is if their bike has a specific configuration that the combo sensor won’t fit.  In particular, these are more popular with unique bikes like recumbent and tandem bikes.

Here for example, is a speed-only sensor from Bontrager:

image

Bontrager also makes a speed sensor that mounts directly into the fork as well, similar to the frame mounted sensors noted below in the next section.

Bontrager also makes a cadence-only sensor, though, these are generally harder to find simply because the demand is so low for them.

image

In both of these situations these singular-function sensors require that the ANT+ head unit supports the single-function device profiles.

Newer bike computers like the Edge 500 and Edge 800 do – but many older units do not, so it’s something to keep in mind.

Frame Integrated Speed/Cadence Sensors:

The last category of speed/cadence sensors out there is the frame integrated sensors.  Technically from an ANT+ standpoint this is merely a speed/cadence combo sensor.  And today, only one company makes them – Bontrager – as part of their Duotrap line.  And further, today only one bike frame vendor  support these – Trek.

That said, for those that have these bikes – these are awesome.  The pod simply fits right into the bike.  I installed one of these on The Girl’s back this past winter…really cool stuff.

IMG_9019IMG_9045

Here’s what it looks like installed into a Trek Speed Concept:

IMG_9092IMG_9103

As you can see above, the design is incredibly streamlined – and perhaps more importantly, not susceptible to getting bumped out of alignment.

Power Meter Speed/Cadence Information:

Finally, it should be mentioned that most cycling power meters will include either speed information, cadence information, or both.

The type of data gathered by these power meters will vary based on how the specific power meter measures its power data.  That in turn drives whether or not speed or cadence data is determined – and if so – whether it’s measured or calculated (estimated).

Take for example crank based power meters (like Quarq and SRM).

IMG_0325

These power meters use magnets to determine cadence – it simply measures each revolution of your crank (the thing your foot ultimately connects to).  Here’s an example of a Quarq Power Meter, with the magnet visible below, attached to a small metal ring near the bottom bracket (taken looking straight down onto the crank & chain rings from above):

image

Then you’ve got other crank power meters like Power2Max, which doesn’t actually use magnets at all – but rather uses mathematical equations to determine your cadence based on other known variables.  In this case, these calculations are usually given a specific cadence range they are accurate to.  For example, the Power2Max is specified as 30 to 180 RPM.

And finally, you’ve got hub based power meters, like the PowerTap, which can do both speed and cadence.  In the case of speed it can measure that directly since it knows revolutions based on hub rotation.  But for cadence, it actually calculates that mathematically.  This is generally pretty accurate, though like the Power2Max it has known ranges or fringe scenarios where it doesn’t work quite as well (really high cadence work).  But for typical everyday use, it’s absolutely more than sufficient.

IMG_5348

In most head unit configurations (that’s the display unit), cadence information from a power meter will always override cadence information from a separate standalone sensor.

Why do you want cadence or speed data anyway?

Well, it depends.  Let’s start with cadence.  There’s actually been quite a bit of research on both sides of the cadence coin.  One side says that a higher cadence – such as 90-95RPM is ideal, while the other side says that a ‘self selected’ cadence is most efficient.  Many folks do high cadence drills though to be able to spin at higher RPM’s in the event it’s required – without taking as large a hit heart-rate wise simply to spin the cranks faster if required (i.e. a sprint to a finish).

Virtually all ANT+ cycling head units will display cadence information in real time on the bike, such as below (see as CAD):

IMG_9174 (2)

During the ride the data is recorded for later access, easily viewable in charts/graphs:

image

Looking at the speed side of the equation, most folks tend to use speed sensors indoors on trainers.  This allows them to gather both speed and distance data when inside.  And while speed and distance while on a trainer is purely a function of your gearing combination and resistance applied by the trainer (meaning, by changing gears and resistance you can dramatically change speed without changing effort) – it can still be an interesting metric for some.

IMG_5476

Afterwards, like cadence, you can view the speed and distance information in charts/graphs:

image

For mountain bikers a speed sensor can be more accurate than GPS in determining distance – as the speed sensor measures speed purely based on revolutions of the wheel and isn’t dependent on GPS correctly tracking on quick switchbacks in forests.

And finally, the same can also be said of indoor track cyclists, who are looking for data in places where GPS isn’t going to work well.

Wrap Up:

As you can see, speed and cadence sensors are both quite common – but also pretty integral to many cyclists.  The good news is that they are pretty cheap, with most ANT+ units costing about $35 – well within the budget of most folks.


To the left are a few different ANT+ speed/cadence sensors that I’ve used and have no problems with.  At this point, I generally recommend some of the quick release variants.  Bontrager came out with the first variant, but it’s been widely rebranded by others, including Motorola.  You can find the Motorola branded one on Amazon.  I use the Bontrager one on my bike day to day and it works perfect (the Motorola branded one is identical).

Garmin GSC-10 ANT+ Speed/Cadence Sensor
Motorola ANT+ Quick Release Speed/Cadence Sensor [Review here for Bontrager branded variant]
Bontrager DuoTrap ANT+ Speed/Cadence Sensor

If you purchase through Clever Training or Amazon you help support the site.  And, with Clever Training you’ll get 10% off your shopping basket.

Hopefully I’ve covered everything you ever wanted to know about speed and cadence sensors – but if not, feel free to drop a note below and I’ll compile it into a Q&A and update the post – similar to what I’ve done on the footpod post.

Thanks for reading!

(Note: I’m currently away on my honeymoon, but due to the magic of automated publishing, you’ll be enjoying content in the meantime.  Thanks for reading!)

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241 Comments

  1. Matt S

    Great writeup, and you solved my mystery about why my Bontrager Speed and Cadence sensors don’t communicate with my Garmin FR305. (yes, I own a dedicated Bontrager Cadence unit). Now that I know about the older combo protocol, I’ll likely pick up the Garmin Speed/Cadence sensor. Thanks again for the help – and congrats on DC Tri!

    • Frank Henley

      What about the Coros Apex Watch ? Is there a ANT that I can put on mu bike that will work with my bike Trainer ???

  2. “In most head unit configurations (that’s the display unit), cadence information from a power meter will always override cadence information from a separate standalone sensor.”

    This is a point I don’t get. Given a hub based power meter, wouldn’t the information of a standalone sensor be more accurate than that of the power meter?

    Also, can you shed some light on the following: Given a Garmin Edge 500 with a Garmin Speed/Cadence sensor and a Powertap hub, can I choose which Cadence information I want to have displayed?

    Thanks for another great post!

  3. Nothing special to say, excepted that I do love your blog!

    Gaby from France

  4. MO

    What I want to know is when the update/new model to the 310xt is coming out. Been waiting for months. Now I have to wait, or better yet should buy the 310xt then surely a new one will be released

  5. Nice write up Ray, I actually recently invested in the Garmin speed/cadence sensor for my 305. I was getting front lower knee pain after longer rides. I realized I was trying to grind to hard by selecting lower gears and slower cadence. Since installing the Garmin sensor I am now keeping my cadence at around 80rpm and the knee pain has completely gone on the longer rides. I need to get used to the higher leg speed but that will come with time.

    Have fun on the honeymoon, see you back in a few weeks.

  6. I’m using a Cadence only sensor at the moment. only because the screw holding the speed sensor onto my garmin gsc-10 came off and the arm ripped off just before my first 70.3 It’s weird to see how inaccurate gps speed is on its own too.

  7. I was thinking to buy the bontrager cadence sensor for the garmin fr305, since it’s cheaper than the Garmin GSC 10.

    Thanks to this post, I saved about £21 by not doing that and go for the garmin sensor at once.

  8. Henrik’s concerns (above) are the same as mine.

    I’m actually in the midst of writing a blog post about the speed sensor arm of the GSC-10. It’s relatively easily damaged and the symptoms can be mistaken for those of a weak battery.

  9. Tri4Success thats exactly what I thought. I ended up changing the battery before the arm came off.

    I also found the garmin sensor got caught on things less when you positioned the arm down instead of up like in the picture above

  10. I can back up Ray’s experiments with modifying the Wahoo Fitness Speed & Cadence sensor to work on a recumbent bicycle. I have it fitted on my own recumbent, a Volae Expedition. In fact, it was Ray who helpfully pointed me towards the Wahoo unit in an E-mail exchange, as it had only just begun shipping when I purchased my recumbent and I’d never even heard of Wahoo Fitness.

    In my case, I used a piece of standard telephone wire to extend the distance between sensors. Soldered each end up properly and wrapped that in a good bit of electrical tape. Sure, it’s not perfectly water proof, but it’s worked a champ since I set it up last fall. The Wahoo also doesn’t have the floppy speed sensor arm that the Garmin unit uses, which is also a plus.

    I’ve used it with both a Forerunner 310XT and an Edge 800 and it gives reliable data from both sensors. (If there were trouble with the length of the extension wire, then I’d expect the cadence sensor to give flaky results. But it’s rock solid.)

  11. Have you seen any evidence of the vector on Garmin-cervelo at the tour yet?

  12. Sorry, that last comment seems well out of place, I just did’t know where else to ask…

    Thanks for all the good work!

  13. Here’s a speed/cadence sensor issue I can’t seem to figure out. I have a Garmin Forerunner 310XT and the Garmin Speed/Cadence Bike Sensor. For some reason the Garmin only picks up the cadence when my bike is on the trainer. But when biking outside, it does record the cadence data. Any clue what’s going on? Last time cadence was recorded outside was April 22.

  14. Thx for the writeup.

    As said by another poster, I do not understand, why the powermeter overrules the cadence sensor, given that the powermeter only calculates the cadence.

    Also I would prefer the gps to measure distance and the sensor to serve as a backup in case the signal is lost.

    For garmin headunits these settings change with different firmwares, but it would be best if the user could choose what overrules what.

  15. Curious why, for the cadence sensor, more people don’t just drop the magnet into the body of the pedal. Cateye’s spoke magnet works as a great option for this and cleans up the appearance of the crank. At least, that’s how I used to roll.

    Great writeup, as usual.

  16. Hi Ray
    Interesting piece, and the comments from others back up my experience with the GSC-10 which are that its arm is a bit flimsy. I have ditched mine and moved to the Bontrager cadence only ANT+ sensor, which my 310XT is perfectly happy with, on both of my bikes (again, with two bikes set up in the 310XT, no problems with two devices) and relying on the GPS for speed.
    As for the magnet arrangement, on my training bike I’m using the rubber band embedded magnet that came with the sensor; on my TT rig I use a rare earth magnet glued to my pedal.
    Thanks for the content, as ever!

  17. Stumbled upon this site last night and proceeded to spend hours pouring over all the info available. Job well done but there is still one question that I cant seem to get answered. I am getting back into multi-sport racing again after a 10 year family, business and burnout break but have been active throughout this time so it shouldnt be that bad but i would like to take my training up a level for competition. I read the 305 review and my question is the following:

    I want to buy the 305 and use it for all 3 tri disciplines. Do I need a speed sensor for training outdoors or will the GPS surfice for getting bike ride info or should I spend the extra cash and get one?

    Thanks for an informative and addictive blog.

    Cheers
    Scott

  18. I recently got a new bike and moved my sensor over to the new bike. I couldn’t figure out why the cadence wasn’t picking up until after looking at your pictures… (I have yet to read the text) The thingy on the pedal is still on my old bike.

    Thanks! I can’t wait to read more about it.

  19. i am using the Bontrager Cadence sensor with the Garmin 800 and it works fine. Have the Garmin combo sensor but don’t like have the arm of the speed sensor standing up on the Pinarello.

    i guess for the winter i will swap out the Cadence sensor install the speed sensor for indoor riding

  20. Hannes

    Happy honeymoon!

    When you are back at home, I really would be happy to read your test of the successor of the 310xt (I am sure it is somewhere out there!). The 610 is not for swimming and my Edge 500 I now have to carry in my hand (see link to velodramatic.com as example). Does the Edge 800 also have this problem? The 800 is larger and heavier, so I assume, that it may even be worse.

    Best wishes from Austria,
    Hannes

  21. @gavtris be careful using just gps for speed. I’ve had speed spikes of 66 mph around some four story buildings. That came from a dropped gps signal.

  22. @Scott Cowan
    Thanks; I’m aware of that risk, but spikes can be ignored, and instantaneous speed, while interesting, isn’t very important to me. What’s more important to me personally is average pace over a training ride, cadence, HR and RPE. When racing, it’s balancing the last three of those in order to minimise my total time. Speed is just a product of those other inputs 🙂
    Had my first significant experience of innacuracy with the 310XT last night, in fact, in a three lap town centre 5k race, where the number of turns and proximity of tall buildings caused an over-distance reading of 250m Much worse than anything I had hitherto experienced with the watch but understandable in the conditions, and still not disastrous at 5%. In comparison, a 10k race in the countryside a couple of weeks back came out at 10,040m, which is a pretty good 0.4% error. (Both were certified courses; I ran as close as possible to the racing line in both.

  23. Anonymous

    I can confirm that the Niterider Wireless Cadence Kit for use with Rebel 3.0, 5.0, 8.0 works with the Garmin 310XT

  24. Anonymous

    hi ray,
    great review
    what i wante dto know is if the garmin speed/cadence sensor works on indoor bikes as well.

  25. Rob

    I’m trying to decide between the garmin speed/cadence sensor and the wahoo one. I keep reading about how the sensor arm is flimsy, gets broken, not reliable if you hit a bump, etc but i can’t find a good head-to-head on both to point out the pro’s/con’s of them. Any suggestions?

  26. Anonymous

    Hi Ray! Kudos to you wonderful insight. Would like to seek your advice, I am a bike commuter and wants to get serious in biking. I am wanting to purchase Xperia Active Phone and match it with either Garmin GSC 10 Speed/Cadence Bike Sensor or Bontrager ANT Digital Standard Speed Sensor. Which do you prefer? Your advice is highly appreciated.

  27. Hi Rob-

    In general, I find unless there’s a structural bike reason to go with one of the non-Garmin sensors (speed only) – that you should go with the GSC-10. The primary reason being that the GSC-10 as a combo sensor is by far the most widely supported. Some of the speed-only and cadence-only devices aren’t as widely supported, for example on the FR305.

  28. Great article, but Do you have any idea that the Garmin GSC 10 Speed/Cadence Bike Sensor will be compatible with the ANT+ of the Sony Ericsson phones, because I have the phone, but I am planning to buy the sensors 🙂

  29. Yes, it’s compatible – no issues there. As long as the sensor is ANT+ (which the GSC-10 is), then it’ll work with any ANT+ compatible device that can read the given sensor type (in this case, Speed/Cadence).

    Fwiw however, I have indeed paired the GSC-10 to the Xperia phones without issue.

  30. The GSC 10 works great – BUT – the cheap plastic clamp that holds the magnet to the spokes tends the stress fracture from vibration. I’ve lost four of these over the past three months.

  31. Thanks for the write up. Can the GSC-10 be used with two seperate head units (ie. Edge 500 for cycling only and a 910XT if I’m racing or doing a brick)?

  32. Dear Mr.DC Rainmaker,

    I like you blog very much, very details sharing on all the gadgets.

    Lately i just bought the Garmin GSC 10 cadence sensor and just fit it to my road bike.

    I also have my Garmin Fr60 watch.

    Few questions here, hopefully you can help me out:

    – do i need to adjust my FR60 (at bike profile – Wheel size) to get the most accurate result?

    – if i need to adjust the bike profile (the wheel size thing), how i know my wheel size? by using measuring tape? or can find it some where from the rim??

    I am just getting started for the road bike, i am still very new to bike issues.

    Thank you.

  33. Hi Ben-

    Yes, you can use the cadence sensor with a limitless number of head units at once. I do this on a near-daily basis while testing devices, for example, having a FR310XT and a FR60 reading from the same sensor.

    Hi CSLoh-

    You’ll find your wheel size on the inside of your wheel on the widewall. That size then correlates to the circumference in mm, which is listed within the GSC-10 manual.

    Enjoy!

  34. Anonymous

    Hello Rainmaker,
    Bontager has a combo speed/cadence sensor coming out on 12/26 for $59.99
    Have you had an opportunity to review this ahead of it’s planned release.
    I’m really interested in getting this combo sensor as I have a 2.1 Trek road bike and a Node 1 computer. At the moment I have the built in speed sensor in the front fork. But I’ve bought a trainer for the winter months and so need a sensor for the rear wheel.
    Thanks.

  35. Hi Mr. Rainmaker,
    I’ve been reading your posts for awhile now. Thank you very much for all your info and reviews!

    I am trying to figure out what kind of speed/cadence sensor to put on my Felt B16 (50cm w/ 650cc wheels). I had planned to put my Sigma setup on it but there just isn’t much room around the crank area for things to fit.

    Here is my question: Will the Garmin speed/cadence sensor work with just an iPod Touch or do I have to get a Garmin compatible product? This sensor looks the most promising given the constraints but I don’t want to spend extra bucks if I don’t have to. I’ve done just a bit of research but haven’t found the answer to this particular question.

    I am also looking at the Cateye Double Strada.

    Thanks.

  36. Tim

    I have a PowerTap Joule ANT+ computer that works fine with my PowerTap hub and just bought the Garmin GSC-10 to use on a second set of wheels. So far the Joule does not want to pair with the Garmin. Following the Joule instructions for pairing. Any suggestions to successfully pair the two? thanks. Good info on your site.

  37. Hi Hoff-

    You’ll need to pickup the Wahoo ANT+ dongle to get it to work with your iPod (or the Garmin ANT+ dongle, but honestly, that one sucks – see my review of it).

    Hi Tim-

    If you’re Joule isn’t pairing, it’s likely because it has an older firmware. The first few firmware versions don’t support the speed/cadence sensor, but the later ones do. No worries though, you can easily download/upate yours. Check out my Joule review on the sidebar, as I actually made note of that exact scenario – I believe I wrote the details of which firmware you needed in there.

    Hope this helps!

  38. Tim

    thanks. I found your instructions on handling a speed/cadence combo and it paired right up. It works great. A great deal for less than $40. Cadence is much more stable than my hub.

  39. Anonymous

    Great blog !

    I have the Garmin 610 and the speed/cadence sensor GSC10.

    While training indoor, it seems I can get the speed and the cadence but not the distance.

    Could you please help me to sort this out ?

    Great thanks in advance,

    Stephane

  40. Hi Stephanie-

    If you get speed readings, it’s very strange you aren’t getting distance readings. Typically, if you get no speed/distance, it’s due to the fact that either the wheel magnet isn’t reading, or that the wheel size isn’t set properly.

    But since you get a speed reading with no distance, that’s rather puzzling. The only other thing I can think of is if your distance isn’t set to total distance, but rather something like “Dist – Last Lap’, which would show the previous lap distance (which would be zero, since it hasn’t happened).

    Wish I had a better answer! A quick ring to Garmin support might also yield an answer, they’re usually rock solid.

  41. Hi Ray-
    I know this is an older post, but have you had any reliability issues with the GSC-10? A guy told me he goes through about one per year. no physical damage, they just stop working. I imagine you’ve had some of these for multiple years. Can you comment on their longevity?

  42. No issues, except for the rare breakage (physical), when/if the unit slides into the wheel spokes and gets decapitated.

    My primary sensor on my bike I’ve had for close to 5 years.

    Any chance he doesn’t realize that you’re supposed to change the battery after a year?

  43. I want to ask one more dumb ANT + profile/Garmin Edge 705 question.

    Can anyone confirm the Garmin Edge 705 is ONLY compatible with the Combo Speed/Cadence sensors, and that it will NOT work with the newer speed-only or cadence-only sensors.

    I get the sense I am right about this, but I can’t find the actual words written here anywhere.

    R.

  44. Hi Mr. Rainmaker,

    Thanks for posting the photos in which you showed how to splice and extend the Wahoo Speed/Cadence sensor. I want to purchase and modify this sensor to fit on my Tomahawk spin bike.

    But there is one more question: how do I modify the speed magnet, which is designed to be screwed onto bike spokes, to be attached to a spin bike’s flywheel? You also mentioned in this article that you were contemplating fitting the Wahoo sensor to a recumbent bike. Have you done so?

    Has anybody else done so? Please kindly share your experience of how to put a speed magnet to a spin bike flywheel.

    Thanks
    Yida

  45. Anonymous

    Thanks a lot for the very prompt response and the detailed explanations,

    Eventually I was able to get it working, the answers really helped even though the trick was actually that I had not started the chrono (the speed and cadence were ok but the distance was not taken),

    Again thanks a lot, great site,

    Stephane

  46. Anonymous

    Why has not some type of sensor been developed to measure speed distance, and cadence for spin bikes with no wheels or small all metal wheels

  47. Antoine

    hello rainmaker. As combo sensor are very cheap and widely supported i would like to mount one paired with a quarq PM. I was wondering if my ant device would let me choose to ignore the cadence sensor from the combo to read only on quarq ?

    In the end is using a crank based PM forces one to use a speed only sensor ?

    Thank you

  48. Correct, Garmin devices will always use the crank-based sensor over the dedicated sensor. There’s currently no way to overwrite that.

  49. Val Tesoro

    I have the Bontrager duo track cadence/speed sensor and the Garmin forerunner 305. Any tips on how I can display the cadence on the FR 305?
    Val
    vtesoro@cox.net

  50. Yup, just go ahead and select to add a Speed/Cadence sensor (pair it) on the FR305. Then in the data fields on the bike setting add a cadence field.

  51. Val

    Thank you for the advice. My FR 305 cadence field is up and running.
    Val

  52. I am just returning a defective Garmin 910XT, after over a dozen Garmin products I have had it with their quality control. I have Garmin GSC 10 sensors on my bikes and a couple of Garmin heart rate straps and a Garmin ANT + usb stick. I am looking at the Suunto Ambit watch as a replacement. Do you know if it is compatible with the Garmin GSC 10 cadence sensor and garmin Heart rate belts and Garmin ANT + usb stick ? Btw thank you for your excelent reviws and web site.

  53. No, they are not compatible with the Ambit. They utilize a Suunto variant of ANT (and not ANT+). Kinda a bummer. There’s some swirling rumors that Suunto may add support for ANT+ devices in the September 2012 Ambit update…but I wouldn’t bet the farm on it.

  54. Well I decided to go with a Garmin 500 bike computer and order the Ambit anyways. FIngers crossed that, at some point in the future, Suunto will adopt the ANT + standard. What tipped me over the edge was that the Ambit is built in Finland and that supposedly has a great build quality and also that the Ambit software is upgrade able.

  55. Hi,

    Have you tried mounting the sensor on the right chain stay? or under the left?

    It seems that the sensor has been designed such that the arm on the sensor can wrap around the chain stay. That will protect it from accidental kicks and getting into the wheel.

  56. EdwinC

    Would it be possible for the Timex Run Trainer to record data from any of these ANT+ bike speed/cadence sensors? The older Timex Ironman Global seems to support them.

  57. No, the Timex Run Trainer doesn’t support the ANT+ SPD/CAD sensor device profile. Bummer indeed.

  58. Hi Ray! thank you very much for the useful information.

    I’m just getting started with triathlons (have just done my first sprint a couple weeks ago). Coming from a running background and a data geek, I really need to start correctly measuring my cycling stats; so finding this review was perfect for me.

    The thing here is I have a 910XT, which I love, however on the bike, it isn’t too comfortable to look at in my wrist and I feel mounting/dismounting may be something else I just don’t want to worry about. So what I want is to get speed/cadence sensor which will be paired to both my 910XT and a simple computer from where I can read my values.

    My questions are, would the Garmin sensor be right for the job? which computer would you recommend?
    I don’t need anything too fancy or expensive, my data recording will be from the 910XT anyways.

  59. Regarding the last post, I’ve been looking at the Bontrager Node 1.1; what do you think about it?

  60. Hi Jonatan-

    Yes, the standard Garmin spd/cad sensor is what you’re looking for. The Garmin sensor is the right option. From a simple computer standpoint, the only ‘cheap’ unit that will read those same sensors is the Bontager Node1/Node2 units. About $70, but would do the trick.

    I have a couple here, and have used them here and there. They work fine, limited of course, but on par with other simple bike computers (albeit cheaper).

    Hope this helps!

  61. Perfect, I think that’s what I’ll be doing. Thanks!

  62. Hi Ray
    I am a paraplegic and have just started handcycling. I am keen on getting cadence info and speed and am thinking of getting the Garmin Edge 500 and the Wahoo speed/cadence sensor. This would have to be cut and extended as the cable is too short to reach the hand cranks. Any advice would be appreciated.

    Sagie, South Africa.

  63. Hi Ray
    is the garmin GSC 10 cadence sensor water-proof ?. Can one cycle in moderately heavy rain ?
    regards
    shekhar

  64. Big T

    Stumbled across this blog by chance, thanks v much for the great info! My plan now is to pair my fr305 with a gsc 10 to use on my rides and on my turbo trainer for distance and speed measurements

  65. Preston

    Ray, do you have any recommendations for a speed/cadence sensor for an indoor bike (spin bike, Airdyne, etc)?

    I’ve been playing around with the Wahoo bluetooth SC rigged up to my Airdyne but it doesn’t work correctly at higher RPMs. Wahoo tech support said maybe the flywheel on the bike is spinning to fast for the sensor to read.

    Thoughts?

  66. Yeah, it’s tough – I’ve been breaking apart a few sensors trying to get some to work the way I want it for hotels/etc – not much luck.

    However, there’s actually been some interesting discussion in the comments of one post over the past few days, check out the bottom of the comments in this:

    link to dcrainmaker.com

  67. Maybe you can help me out here. I’m looking for a speed only sensor that is not as obtrusive as the standard Garmin speed/cadence sensor. I do not need cadence as my power meter can measure cadence instead. I’m looking for something that only needs to measure speed but more importantly is more subtle and less obtrusive than the Garmin rig. Thanks Steve

  68. Yeah, there’s not many good looking options there. You can pickup a speed-only sensor – but honestly it’s the same size as the dual sensors. The Bontrager quick-release one is nice, a diferent styling, and may appeal to you more. I wrote up a review on it here:

    link to dcrainmaker.com

  69. I just purchased a Garmin Edge 500 to replace a 305. I ride a recumbent trike so I started to modify the Garmin Speed/Cadence sensor. I have soldered on to the two wires after removing the speed sensor, and am using a Cateye speed sensor attached to the two wires. Do you think this will work as well as the Wahoo Speed/Cadence sensor you show?

  70. Hi thanks for helping to explain the complicated world of ANT+ speed and cadence sensors. I want to make things slightly more complicated because there is now a ANT+ kayak cadence sensor that attaches to your paddle and sends wireless kayak cadence data to any ANT+ GPS device that can also receiver the cycling cadence data. It will work with both the speed/cadence protocol and the cadence only protocol. Runners and Cyclists have had the benefits of cadence data for years and now kayakers can too. It’s called the Vaaka kayak cadence sensor so any multipsort athletes out check it out on google.

  71. Hi DCRainmaker. Quick question – I recently got the Garmin GC10 to pair with my Timex Global Trainer and I find that my speed and distance are way off – a 32km ride according to GPS, but the reading from the sensor it is telling me more like 22km. Also speed is obviously out of whack – I’m slow, but not that slow! Any idea on how to correct this or how to just use to measure cadence? Any help would be much appreciated!

    Thanks

  72. Yup, on the bike settings on the TGT you’ll want to set the correct wheel circumference.

  73. Anonymous

    I’ve just ordered a Suunto t3d (since its out of production I got it for almost half the usual retail price). Part of why I choose this model was the possibility of adding all the extra goodies. Suunto’s Extras are on the expensive side, and after reading the posts on the Ambit I guess that there is no way that the t3d will work with the Garmin Speed/Cadence sensor.

    Is the best way to confirm this to actually try it?

    Johan P.

  74. I have Suunto dongle, can I connect sensor like these directly to PC without use of some headunit?

  75. RE: Suunto t3d

    No, none at all, completely different protocols, sorry!

    Hi Marwooj-
    RE: Suunto Movescount Stick

    Yup, you could use something like TrainerRoad and it would work.

  76. I had (just returned) B’TWIN ANT+ speed/rate sensor, no way to pair this with anything (have visited decathlon and it could not even pair with their own staff), hard to find anything in Poland not expensive.
    Is garmin one Zero/Nada problem usable?

    • pepe

      Well, in december 2012, geonaute, silently, changed the Geonaute B’TWIN ANT+ speed/cadence sensor.

      Pre 12/2012 Geonaute B’TWIN ANT+ speed/cadence sensors where invisible to many units/apps,

      Units produced after 12/2012 are fully visible to the most units/apps.

  77. Interesting site thanks!I’m about to buy a Montana 600 GPS for my Quest XS (A fast fully faired recumbent trike) I want monitors for heart rate and Cadence-(speed can come from the GPS)The front wheels are shielded from the GPS by Carbon fibre wheel wells(part of the monocoque body) What ANT+ devices would you recommend?

  78. Anonymous

    Do you know why my Edge 500 started recording cadence without there being a sensor on the bike. It started half way through a ride after I’d hit the Lap button. I do have cadence sensors for other bikes but not this one. Thanks for any help you can give.

  79. I have the Timex Global Trainer and just added the GSC 10. For some reason, it will only capture distance from the speed/cadence sensor when the GPS is on and the GSC 10 is paired. Is there a way for it to capture both the GPS map and the speed/cadence data?

  80. Lee

    Rather than sticking it upwards like in the photos, I have rotated the speed sensor on my GSC-10 all the way downwards so it’s resting on the chainstay. This makes it less susceptible to being caught and snapping off when putting the wheel in & out.

  81. Raj Gupta

    Hi rainmaker,

    I think you have already answered this question for Sony phones but just to be double sure – will gsc 10 pair up with wahoo fitness app or strava app running on my iPhone 5 ? iPhone 5 supports ant+ / Bluetooth 4 and I am using wahoo fitness App with wahoo heart rate monitor already.

    Thanks for your help in advance.

    • DC Rainmaker

      Yes, it will – but ONLY with the Wahoo Fitness dongle. The iPhone 5 doesn’t have native ANT+ in it (it only has Bluetooth Smart via Bluetooth 4.0 in it). In fact, no apple products have ANT+ within them, they all need the Wahoo Fitness accessory. That accessory does work with the iPhone 5 legacy adapter.

      Hope this helps!

  82. John Highet

    I recently bought a new Garmin Montana 600 to use on my Quest velomobile. (A fully faired fast recumbent trike) The Montana ONLY supports Cadence, Temperature and Heart Rate however according to the various websites it needs a COMBINATION cadence speed sensor and will not take data from a single Cadence sensor like the Bontrager offering.After a bit of research I bought a (cheap) Garmin GSC-10 and managed to attach it to the front subframe using cable ties and actually using the movable speed pickup as a tie-down point. (The speed function is ignored anyway) Instead of the Garmin crank magnet I used a small stack of 12mm dia x 2mm thick Neodymium Magnets which self attach to the end of the pedal spindle. They are so powerful that they need no other attachment and can also cope with a greater gap from the sensor– it works perfectly! If anyone wants a photo then contact me here.

  83. RTO

    Great info on every review.

    Question- Is it possible to mount the Garmin GSC-10 (or the other devices) upside down on the bottom to help prevent that sensor arm from getting annihilated with any contact into the downward travelling spokes from any flex or a nudge? I read that the arm is supposed to be within 1/8″ from the spoke magnet. Yipes…

    Seems like all the speed/cadence sensors should all be mounted on the bottom for that reason…

  84. ml

    is there a chance that the garmin combo might work in the future with the ironman/gps/heart watch with a firmware update, as your review states at that time it does not work with it?

    • DC Rainmaker

      Technically it’s possible, but I don’t see at as likely unfortunately. The product was introduced over a year ago now, and for the most part that team is likely focusing on new efforts.

  85. Joel

    I recently got a Garmin 310XT and decided I might as well use a cadence sensor.
    I bought the Niterider sensor because it was the cheapest.
    On my first ride with it today about 25% of the time I got no cadence reading.
    I tried adjusting the position of the sensor to the magnet but that did not seem to help.
    I ordered an Icarus magnet to try since it is stronger.
    Any ideas what he problem is?

  86. Doug B.

    Regarding Todd Moses’ post of Nov 18, 2012…I too am wondering that as of today. I got the TGT for X-mas and have slowly been working with all of the features little-by-little, with still more to investigate and your website here is a big help. Today the weather was good enough to get off the trainer and take the bike on the road again. I used the GSC10 sensor with the TGT. Downloaded the workout and was disappointed (albeit half-expected it though) to find that the route didn’t map out even though the GPS was acquired before I started rolling. So…does using a speed/cadence sensor completely override the GPS or are Todd and I missing something? I would very much like to have not just the routes mapped but the altitude information that comes along with it. And if the sensor does mean that the GPS is overridden, does that also happen with the Garmin devices? (I have the TGT and and it has more functions than the wired computer I’d been using so I’m not going to ditch the TGT and pay several hundred $ for a Garmin just to map my rides, but I figure anyone shopping may want to consider if it’s the same situation for both brands or just with the Timex.) Cheers, and thanks for your help.

  87. Franser

    Hi Rainmaker,
    it is possible to an edge 500 with a speed sensor and a Bontrager Bontrager Cadence sensor to operate at the same time, two individual devices at the same time.

    Thank you

    Franser

  88. Keimpe

    Hi, I was wondering, I have a Garmin 910 xt and the Garmin GSC-10. Do you need to mount the wheel magnet as you already have speed with the GPS?

    Regards

    • DC Rainmaker

      You don’t need to, but I would. The reason is that if the GPS fall out (tunnel, etc..), then it’ll use the speed sensor instead. But if that shows zero, then it’ll have weird drops.

  89. Kathy

    First off, THANKS for all the reviews and information that you provide.

    My question is regarding the GSC 10 speed/cadence sensor and durability. I have read reviews that complain about the unit not being water proof / resistant. I would be putting this on a mountain bike and can guarantee that it would get wet from either creek crossings, rain or from washing the bike. Have you found this to be an issue?

    Thank you!

    • DC Rainmaker

      It’s definitely water resistant (I’ve had years of rain on mine).

      Most issues I hear from mountain bikers tend to come from dirt or mud getting caked on the sensor, and then the sensor sliding into the rear spokes and then being sheared off. :-/

  90. Ireneo

    Got a idea whether Garmin Garmin GSC-10 Speed & Cadence Sensor works with Garmin Forerunner 310xt? I learned from Garmin that it is not listed as one of the compatible devices. Thanks!
    link to buy.garmin.com

  91. Terri Cawley

    My Garmin 310 XT stopped giving a read on the “Distance” while indoors on the bike trainer and outdoors as well. The GSC-10 Speed/Cadence sensor is working for those two fields. What do I do to get it working again?

    Thanks, I really enjoy your blogs and I bought my watch/HR monitor based upon alot of your research. We really appreciate you.

    • DC Rainmaker

      Double-check that cadence is working. If cadence is working, then it’s not the battery. If it isn’t working, it’s either the battery, or the unit just became unpaired and needs to be re-paired. Alternatively, you may have accidentally switched bike profiles.

      Next, double check that as the wheel magnet passes the sensor arm, the light illuminates. If not, it may have just been out of adjustment – simply move it back in place. Failing all that, it may mean that your speed sensor arm got bonked/whacked and you may need a call to Garmin support.

  92. pepe

    Geonaute B’TWIN ANT+ speed/cadence sensor Ref: 8181211 is the only readily available and cheap ANT+ speed/cadence sensor (19.95€, 16.99£), through european stores.

    Be careful thought:
    Pre 12/2012 Geonaute B’TWIN ANT+ speed/cadence sensors where invisible to many other units/apps. (Garmin Edge 500 was working with it trough device id manual setup, IpBike fully compatible).

    Units produced after 12/2012 are fully visible to the most units/apps.

    Test before buy

    • Wojtek

      Pepe can you help me with connetion B’TWIN ANT+ speed/cadence sensor to my Sony Ericsson Xperia Arc S? I try many combinations and slowly loose my patience 🙂

  93. mpulsiv

    I’m still a bit confused. Can I use GSC-10 without GPS feature on my Forerunner 610? IMHO. I’d like to treat GSC-10 as indoor training device but will be using it outdoors because I have no faith in GPS accuracy!
    Best thing since slice of bread is wired Kinetic computer (manually calibrated by measuring distance of full spin with me sitting on a bike). Kinetic has been dead accurate compared to GPS on Forerunner 610. I have been running both of them side-by-side for over 2000 miles. link to kurtkinetic.com

  94. VeloEric

    Just installed a Quarq Riken PM on my bike, using my Garmin 800 as the head unit. Do I still need to use the Garmin speed/cadence sensor? Won’t I now get speed from the GPS and cadence from the quarq?

    • DC Rainmaker

      Not for outside. The Quarq will provide cadence for inside/outside, and the Garmin will provide distance outside. Inside on a trainer, if you wanted speed/distance, you’d want to keep on the GSC10.

  95. James Freeman

    Just a quick question, I have a power2max is there anyway of using the cadence from the p2m and the speed from the GSC-10 ? Only reason I ask is I have experienced a couple of drop outs in power readings and p2m reccomended me to use the power2max for cadence but also wanted accurate speed readings (indoor and out).

    • No, you can’t change it unfortunately (at least with Garmin Edge units). Cadence from the GSC-10 will always override a PM. However, it will still use the speed channel indoors.

  96. James Freeman

    Actually I just tried removing my magnet from the pedal spin and cadence read 0 for about 10 seconds and then it automatically started picking it up from the p2m, RESULT!! 😀

  97. pepe

    Wojtek, in December 2012, Decathlon, changed the Geonaute B’TWIN ANT+ speed/cadence sensor.

    Pre 12/2012 Decathlon Geonaute B’TWIN ANT+ speed/cadence sensors, as Ifor noted: “have the pairing bit set which of course means most display units fail to find it when doing a wildcard search. If the display allows a manual setup then if you know the Device ID you can set it up manually and it then looks to work.”

    Android IpBike and Windows “ctAnt+ trail” detects this sensor´s ant Device ID and can pair with it automatically, allowing manual Device ID setup for other units/apps. (Those who have that option).

    Units produced after 12/2012 are fully visible units/apps, and are listed in Ant+ directory: link to thisisant.com

    If you ask for, Decathlon will exchange the old unit for a After 12/2012 one: link to decathlon.fr

    “Ma garmin 910 xt ne reconnait pas ce compteur de cadence qui pourtant affiche compatible avec ANT+.
    Dommage car le prix est attractif et c’est facile a fixer.

    Réponse de la marque

    Ce capteur est maintenant 100% compatible ANT+.
    Donc sauf encore vieux stock en magasin de la version précédente, ça doit fonctionner.
    Je vous inviter à le retourner en magasin pour échange et profitez en pour faire le test sur place.

    Cordialement.

    Christophe Leclerc
    Chef de produit Accessoires – Product Manager SOFT – B’twin”

  98. Kiwi Steve

    Hi, I’ve been using the Garmin GSC-10 with my Garmin Forerunner 910XT on the wind trainer and it has worked well for speed/distance/cadence. I got out on the road yesterday with it for the first time + had my GPS turned on because I wanted map and altitude info.

    For my ride Garmin Connect shows speed and cadence info (presumably from the GSC-10) and I got a map of my ride (GPS signal), but I had no elevation data. Well…I say no elevation data, my elevaton chart was a flat line for the entire 62km ride, yet the flat line was at 9200m, even though I spent a lot of the ride down at sea level.

    Any idea how to get elevation data and a map when using the GSC-10, or do you suggest simply using GPS data when on the road, and only using the GSC-10 for indoor training?

    Cheers,
    Steve
    Ps. Love your posts about Garmin Forerunners

  99. BQ

    The other day I ordered the Suunto Cadence pod to go along with my Ambit. After having explored your site a bit, it looks like I could save money and get both speed/cadence from the same pod by ordering a different pod. Any reason (other than the hassle factor) not to send my cadence pod back to Amazon and get a Garmin or Motorola pod that does both for less $$?

    • Definitely return and get the Garmin or Motorola pod. You’ll save money, and then it’ll be compatible with other units. There’s only a handful of bikes out there that don’t work with the combo pods, mostly falling into either the tandem category, or some really rate high-end triathlon bikes with weird layouts near the wheels. 99% chance says you’ll be good.

  100. BQ

    Thanks for the feedback. Any reason to pick one of those over the other? I like the idea of not using zip ties, so that might push me towards the motorola. Also, finally, does the use of a combo pod automatically override the GPS distance on my ambit?

  101. Michael

    Been reading your blogs to see how you set up to use the Garmin 910XT and the Wahoo KICKR sensors but couldn’t find it. Sorry if this was already asked. Currently I have th Wahoo SC on my bike. If I install the Garmin GSC 10 can I use that to also use the Wahoo KICKR? What would you recommend?

  102. Michael

    Ray,

    Would you recommend using the Wahoo SC or the GSC 10 trying to incorporate Kinomap, Wahoo KICKR & the Garmin 910 XT? I appreciate your feedback. I’m new to all this technology and cycling.

    • The GSC-10 would require that you also have the Wahoo ANT+ iPhone dongle if you’re going to use the Wahoo KICKR and/or Kinomap. That’s because those are all ANT+, versus Bluetooth Smart.

      Meanwhile, if you’re going with the Wahoo Blue SC, it’ll work with the KICKR app and Kinomap natively, but won’t work at all with the FR910XT.

      Right now you’re kinda stuck between two technologies. If it were me, I’d go with the GSC-10 and then pickup the Wahoo iPhone adapter.

  103. Dustin

    Hi Ray! I have the 910XT and the Edge 800 on my TT bike. On my long distance races (iron and half-iron) the 800 will lose connection to the Garmin speed/cadence sensor, but will remain connected on the 910XT. I have to rescan on the 800 mid-race to get reconnected to the speed/cadence sensor. What do you think is happening here?

    • This sounds like perhaps a connectivity issue with distance. I’ve seen that in rare cases. The first thing I’d try doing for fun is swapping the battery. You may be getting low, and while that typically doesn’t impact signal strength – it’s worth a try, and will only cost about $2.

      Beyond that, rescanning shouldn’t actually help, as it should just re-pick it back up as soon as it sees it again. Which almost makes me think you may be having some other issue on the 800. One thing to try would be a soft-reset, which sorta cleans up the Edge 800 but keeps your data files. Failing that, you could do a hard reset, which resets it back to factory state.

      I have a strong feeling one of those two will solve it if it’s not a signal issue.

  104. BENN SHEPHERD

    Rainmaker,
    Your web site is fantastic and I use it more than the documentation that comes with the devices I am addicted to! I have just allowed myself a 910XT after a horrible Triathlon in Bretagne (36 degrees). My question is this:
    I want to use the Garmin Cadence Sensor with my EDGE 500 and the 910 XT and the HRM. It seems that when I pair the Cadence Sensor with the 910XT that I loose the pairing with the Edge 500. I want to use both the EDGE to watch my stats while racing and obviously wear the watch for the whole race and keep all data. Do I really need 2 cadence sensors? I have wondered on some races why some guys have 2 and maybe it is for this reason? Apologies in advance if the answer is obvious.
    Let me know if you are in Normandy and fancy a ride mate and thanks in advance for any reply.
    Benn

  105. David Cusick

    Hi, ditto on the comments about what a great site, you address the questions that instruction booklets and user guides seem to gloss over at best, but most of the time don’t even mention. Anyway, enough said about the fantastic service you provide and onto the question …. I have just bought a Garmin Edge 510 for my wifes’ Scott and when fitting the GS10 to the Frame opposite the chainstay (as you mention, bit of a pain making sure it all lines up etc) I notice that the rubber pad at the base of the unit where it’s shaped to fit the contour of the frame, is nothing like it ! Granted, it probably fits most but that part of the frame on the Scott CR1 Contessa is quite broad and flat so the shaped/curved pad at the base of the unit doesn’t sit particularly well and as much as I have tightened the cable straps as much as I can, it feels like it’s going to be more prone to moving out of alignment when riding the lumps and bumps of our not so perfect roads here in the UK. Any suggestions ? ….. By the way, we don’t need the speed arm of the unit as we’ll be picking up speed from the GPS, we only need cadence so I may be looking for another Cadence only unit anyway !

  106. John

    Great info, thanks. One question – is it possible to set 310xt to override “GPS” speed to be speed calculated from magnet, but still use GPS for tracking? I ride amongst tall buildings and speed bounces around a bit. Thanks

    John

  107. Windsor Cannon II

    I have a cateye V3 biek computer with its speed/cadence and heart rate monitor. With a ANT+ attachment to my iphone, can it read my original sensors or do i need new ANT+ sensors?

  108. Anthony Kingren

    Hi Ray,

    I just purchased a Wahoo KICKR and I am trying to get cadence from a GSC10 and heart rate from the heart rate strap from my Edge 500 to appear in the Wahoo Fitness app on my iphone 5. I have a Garmin ANT+ stick from my Forerunner 410 watch, but the stick does not look like any one that I have seen on your site (I am sure it is there somewhere and I just haven’t found it). It is more pill shaped and is says Garmin lengthwise on the top. Do you think if i get an adapter to connect this ANT+ stick to my iphone 5 my heart rate and cadence will appear in the Wahoo Fitness app? If not will the wahoo fitness key upload from those two sensors? Any advice would be greatly appreciated. Thanks.

    Anthony

    • HI Anthony-

      With your FR410, it came with the new sticks that were released this past spring. Work the same though, just tiny.

      As for the iPhone, yup, you’ll need the Wahoo ANT+ adapter as well as a Lightning adapter (they work together). At which point you’ll be good to go and the data will show. One minor note on the Lightning adapter, Be a bit careful with the cheaper knockoffs, Wahoo has found that some of the non-Apple official ones don’t work well (if at all). 🙁

  109. Anthony Kingren

    Ray,

    Thanks for the quick response. I was hoping to get around buying a wahoo fitness key, but what are you going to do. Thanks again.

    Anthony

  110. Lauren

    will the Garmin speed/cadence sensor work with the Timex Cycle trainer 2.0?
    thank you

  111. Mário

    The Wahoo Speed/Cadence sensor is compatible with Garmin 910xt or suunto ambit 2?

  112. Jeff

    Do you know if the Forerunner 310XT or the 910XT support the single-function cadence and speed sensors?

    I recently got a good deal on a used Lemond Revolution and I’m hoping to track both. My old 305 is one good rain away from certain death, so I’m due for an upgrade soon.

    • Offhand I know the 910XT does, but I can’t remember if the 310XT does. Have to go dig it out and charge it up.

    • Jeff

      Cool, thanks. Googling around I saw some references to someone misconfiguring a 310 and it was only showing speed, so it sounds like it does. Now, I’m just waiting for a 310XT Cyber Monday deal ..

      FYI, I tried subscribing to followups to this page and confirmed the link when I got it, but never got the email that there had been more replies. Cheers!

    • Hmm, strange.

      Btw, there’s a very sweet FR310XT deal today for $159 with the HR strap.

    • Jeff

      Nice! Wasn’t planning to get the model with hr, but that works.

  113. ELI

    WHEN CHANGING THE BATTERY ON THE SPEED/CADENCE SENSOR THE THIN GASKET AROUND IT BROKE
    WHERE CAN I GET A REPLACEMENT?

  114. hagai

    Hi there; you seem to know a lot about the topics so here is one for you: I have a suunto 2s, the company and other distributer have run our of suunto cadence pods; which other cadence pods can work with suunto ambit 2s? Many thanks for your help.

  115. Bivey

    Ray,

    Love the site. Thanks so much for all of, well, all of this. Having trouble coming up with an answer to my GSC10 not picking up on my trainer. I have a KICKR, which as you know, has no real wheel assembly. Does that mean the GSC doesn’t turn itself on because the “speed” magnet is absent? Is there a way to get the cadence to pick up while the real wheel is off of the bike?

    Thanks!

  116. Andy W

    Very useful article – answers the point I was puzzled by, as I didn’t understand why when you have speed&cadence sensing, you’d want only speed, or only cadence.

    One comment – I recognise that this is an older article, but you state that Trek Duotrap is the only frame-integrated system : now there’s also Giant RideSense at the least, maybe other brands too.

    • Yeah, since then there’s a Giant and a couple of others that have it. Some are logical (such as in the rear portion of the frame), but others are silly, like a Trek one I have on my road bike that’s in the front wheel (thus useless on a trainer).

  117. Harris

    I just purchased the Minoura LR760 and ready to get all the required accessories. I know I have to get the Minoura dongle to work with iPhone. My question, will the Garmin GSC-10 work with the dongle and the LiveTraining app? The Minoura site says LiveTraining works with any ANT+ sensors except Garmin and Digifit. But, if you continue reading down the LiveTraining page, it only calls out Digifit. I am thinking about the Garmin sensors so I am covered when I decide on a dedicated device (Edge).

    Last question, will other sensors work with a Garmin device like the Edge? I

    • It works with the Garmin sensors. I think they’re a bit confused. It’s the Garmin & Digifit iPhone adapters that only work with their respective apps. From an ANT+ sensor standpoint (like the GSC-10), it works with every ANT+ device on the planet (I’m aware of no device/app it fails with).

      And yup, the GSC-10 will work with the Edge concurrently at the same time.

      Enjoy!

  118. Harris

    Thanks for the quick reply, wow….awesome. I just found a great deal on Wahoo’s site for a bike pack that includes the sensors and iphone 4 Ant+ case…. Now I just may have to pull the trigger on it.

  119. Harris

    Forgot the question, any experience with the wahoo speed and cadence sensors? Great deal if some confidence in their sensors.

    • I’ve played with them a little bit. They are two-part sensors (unless you’re talking the BlueSC, which I have lots of experience with – all good there). That said, on the ANT+ sensors, I haven’t heard any complaints and they’ve been out a few years.

  120. Harris

    Yeah, the two part is the only thing I hesitate on… Thanks so much for your posts, responses and just being willing to help.

    • Yeah, it can be a slight downside, but also an upside if you’re bike is ‘complicated’. I actually cut one apart and extended it with some wiring from Home Depot once for an experiment (the Wahoo one) on how recumbent could be done. Kinda fun…

  121. Harris

    Decisions…decisions. Definitely torn between the good deal ($70 for sensors and dongle) and wanting the GSC-10. To complicate the purchase, they also have wahoo dongle and heart rate strap at a killer price.

  122. BlinkyPete

    Can anyone confirm the Garmin Edge 705 is ONLY compatible with the Combo Speed/Cadence sensors, and that it will NOT work with the newer speed-only or cadence-only sensors.

    I get the sense I am right about this, but I can’t find the actual words written here anywhere.

  123. Al

    Hello,
    I love reading your reviews! Thank you for them,
    I have a Garmin gsc 10 on my bike, I have paired it with my Harmon 401 and with my Oregon, and they only read cadence. The distance is always way off since I ride mainly in thick woods with a lot of switch backs. I had the same issue on other Garmins.
    How do you get them to display the distance of the gsc10 and not the GPS?
    I appreciate anybody’s help in this,garmin keeps telling me I have to buy an edge. Which I refuse to, I already have four Garmins, don’t need one more, and I know the unit is trading the data, I just hides it from me!
    Thanks
    Al

    • Unfortunately, I’m not too familiar with the Oregon series, or Harmon. I don’t believe those units though have the option to change device source. Can you shut off the GPS on them? That would at least force it to the sensor, but I don’t know whether or not it uses speed sensor data at all.

  124. Al

    Salut!
    Merci! That was a fast reply.
    Sorry, I didn’t catch the autocorrect feature, I meant the Garmin Foretrex 401, that has barometer and ANT+.
    Neither this one or the Oregon (just like a Dakota with a bigger screen) show a way to get the GPS off or read the speed of the GSC-10, but they recognize it can give speed and show the cadence fine.
    Do all the gps/watches you check that have ANT+ have the ability to read the speed/distance from the GSC-10 instead of the gps? Would be nice if we could read the distance from the sensor (that actually just counts how many times the magnet goes by the receiver) and the GPS was on to be able to map the ride, even if it is not that accurate.
    Thanks again.
    Au revoir!

    • Pretty much all do, except the budget ones that don’t have any ANT+ at all (like the Edge 200 or FR10). However, the others that do generally still use GPS for recorded speed/distance, and just use the sensor for instant-speed instead.

  125. Ryan

    Is there a way to transfer information from my bontrager node 1.1 to strava? I also have a garmin 310, but it doesn’t get the cadence. The info would be useful as I just got a trainer and would like to get more information than just my HR from my 310. The node has everything I want, I just want it to transfer to strava. I have a Bontrager duo track cadence/speed sensor on my madone 5.1

  126. Jeffrey Grabinski

    Any idea why 2 people riding a Trainer Road wko using Ant+ cadence/speed would finish with the exact same distance covered on the Garmin at the finish despite one rider having 3 RPMs AND 78 watts averages more than the other rider for the entire wko? Thanks.

    • Yup, all about gearing. I can produce identical speeds with different gears. Different gears also can mean different speeds and thus difference cadences and different wattages.

    • Jeff

      I understand that you can spin faster in an easier gear and go just as fast as someone spinning slower in a tougher gear…. But if someone was spinning FASTER AND producing more watts (harder gear/better Pedal stroke)…. Wouldn’t that person go farther???

    • Not if the resistance is different. Even a single turn of the knob (depending on type of trainer) can easily be 10% more/less. Same goes for tire pressure, tire type, etc… It’s surprising how many things play a factor in it.

      Ultimately, the singular challenge with Trainer Road is that unless you’re using a CompuTrainer/KICKR/PowerBeam, there’s no calibration aspect on the trainer – so it’s a bit of a swag (which they’ll happily admit to).

  127. Tim Daloisio

    I currently have the Wahoo Blue SC on my bike paired with the Blue HR and the RFLKT which I like. But I am just getting into Trainer Road and don’t love the idea of having to repair the bluetooth between the phone and the laptop everytime I want to use it. I have a Garmin ANT+ stick and HRM from my Garmin 405 GPS kit. I’ve gotten that to pair to Trainer Road. If I want to use a Garmin GSC-10 ANT+ speed/cadence meter, will it work with the Wahoo Blue SC magnets? Or would I have to swap out the magnets to? (which would be a silly amount of work and make me rethink things again).

    Thoughts?

  128. Claudio

    Today I was at decathlon (french sports shop which you find all over Europe) and I picked up a b’twin branded ANT+ cadence/speed sensor for just 19€95 (b’twin is the decathlon brand for bike-related stuff). It looks very much like the Wahoo sensor you show in your post, with two separate units and a wire connecting them. I installed it in about 20s (it uses rubber bands to attach the two units to the bike frame), and I paired it with my 910XT without any problems. Link to the product page in French or in English (UK site).
    Had been hesitating for a long time on getting one of these, but when I saw the price, i didn’t resist one second!

  129. Luke

    DC – after some help here – purchased a cycleops powertap speed and cadence sensor – identical to the wahoo model in this post.Just in the initial setup phase of using my cycleops fluid 2 with virtual training on my ipad – seems at the moment I can’t get the speed and cadence sensor to turn on, it might be something simple but the instructions that come with it are just how to install – do i need to replace the battery, flick an activation switch within the sensor itself…it seems you have been able to link yours with your iphone so wanted to ask – I have the wahoo ant+ dongle on the ipad but its just not picking up the sensor…..

    • Sounds like battery. Sometimes, rarely, but enough that I hear about it, the unit gets set in an on-state in shipping/stock, and basically burns through the battery. Try swapping that out, and then go from there. It’s a cheap $2 replace from the drug store.

  130. heather

    What setting have I messed up that my cadence/speed device only does speed distance? I really need cadence.

    • There’s not any setting that makes it zero. Typically, that’s caused by the magnet getting slightly out of alignment. Validate the light illuminates when it goes past, and that the ‘Cadence’ data field is on the display.

    • heather

      Thanks for the response. It was less than a hair off. Working great now.

  131. Michel Chevalier

    Mr. Rainmaker,

    I enjoy your site a lot. Thanks for taking time to share your impressive knowledge with us.

    Just sold my road machine, and got myself one of those clever Brompton folding bikes. This bike configuration being anything but standard, there is no way to install my GSC-10 so it reads both cadence and speed. It’s one or the other. Right now, is’t picking up cadence only. Does it make sense if I install, along with the GSC-10, a third party ANT+ speed-only sensor?

    Would I be able to pair both sensors, with the 910XT? Or should I get a Whaoo, and go ahead with the modification you suggest?

    Thank you again.
    Michel

    • Hmm, the 910XT does support speed-only and cadence-only sensors, so you could go in that direction. The challenge with going with a combo + a speed/only is that it’ll likely only read the combo, resulting in a wonky value for speed.

  132. Doug B

    I currently have a Powertap G3, GSC-10 (aquired before I bought the Powertap) and use them with an Edge 500 and a 910xt. I’m trying to figure out if there is ANY benefit to keeping the GSC-10 on my bike, or if I am better off just removing it and using the Powertap exclusively for speed/ cadence information while inside, and cadence while outside? Remember, I already own both, so the cost isn’t really a factor here, just which option is better, lighter, more reliable, etc.

    Thanks, love your site!

    • The GSC-10 will be more reliable for cadence in really high ranges (i.e. above 150RPM), but for 99% of day to day riding, no reason to have it on there give your setup.

    • Torsten

      I’ve been starting using Powertap SL2.4 meanwhile four years ago – never had any problems. However, in order to make it ANT+-compatible, I’m planning to replace the speedhub’s internals to G3 (price tag for that is 380€ [Sportimport/Germany]). In the past, I’ve been using Powertap Cervo as computer, which will also be replaced by Navi2Coach. Question: do speed and cadence just appear as seperate ANT-sensors or how is the data transmitted? Cervo also shows this data but in fact I never concerned how that really works 🙂

  133. Good day!
    I’m interested in, and this sensor will work with Suunto Ambit2?

  134. Hans

    I have a garmin gsc 10 speed/cadence sensor and able to pair with my Timex Cycling trainer. Thanks to your blog I am able to get very useful information and decide what I need.

    What I am curious how can I get the speed/cadence data to mapmyride app as they have sensor capability. I believe right now only Wahoo rflx+ capable doing so as the computer is ant+ and via Bluetooth 4.0 able to transmit to iPhone.

    Please enlighten me of you have any good workaround.

  135. Hans

    I have a garmin gsc 10 speed/cadence sensor and able to pair with my Timex Cycling trainer. Thanks to your blog.

    What I am curious how can I get the speed/cadence data to mapmyride app as they have sensor capability. I believe right now only Wahoo rflx+ capable doing so as the computer is ant+ and via Bluetooth 4.0 able to transmit to iPhone.

    Please enlighten me of you have any good workaround.

  136. Marcelo

    I have a Garmin Fenix 2 and was about to buy the garmin gsc speed/cadence sensor, but read lots of folks complaining about it being very non water resistant. That made me look into other options, and so far i guess the bontrager ant+ interchangable, and the wahoo ant+ cycling speed/cadence sensors are my other choices. Have any recomendations?

  137. Adam Suhy

    I have a Garmin Forerunner 305, and the GCS cadence/speed sensor. Do you know of any cheap receivers that will read the ANT+ signal (don’t care as much about GPS) that I could use for my longer rides? My Garmin won’t last long enough, and I’d rather have more data and less GPS if I can.

    • The cheapest recording-capable devices would be the FR60 or FR70 watches (last a year on a single battery). No GPS data there, just SPD/CAD sensor support.

    • Adam Suhy

      Thanks, awesome! Any other branded items that you could suggest? I’d also be OK with a handlebar mounted dedicated bike computer as well.

    • Check out the Bontrager Node1/Node2. They don’t record the data for download, but do keep track. Sorta ideal for commuter bikes. Beyond that, it’d really be phone apps with adapters (if ANT+).

    • Adam Suhy

      Thanks, between those I’ll find something in my price range, I’m sure. Thanks!

  138. Darren

    Wondering what bike sensor to get that will go with my sunto ambit 2

  139. Andres

    Is there a way to set the garmin computer (910xt) to ignore really high cadence? similarly to the way you can set it to ignore 0 cadence when calculating averages? The reason why is because when I go really fast downhill and Im coasting the sensor on the crank is right around the sensor on the bike, and slightly moving the crank up/down is making it think I have a cadence of 200+. I have tried coasting with the cranks on the opposite position, and I dont get those really high ridiculous cadence, but I dont feel as well balanced on the bike and cant go as fast downhill as I know I can.

    Thanks, Andres

  140. Andres

    Is there a way to set the garmin computer (910xt) to ignore really high cadence? similarly to the way you can set it to ignore 0 cadence when calculating averages? The reason why is because when I go really fast downhill and Im coasting the sensor on the crank is right around the sensor on the bike, and slightly moving the crank up/down is making it think I have a cadence of 200+. I have tried coasting with the cranks on the opposite position, and I dont get those really high ridiculous cadence, but I dont feel as well balanced on the bike and cant go as fast downhill as I know I can

    Thanks, Andres

  141. Tom

    Can I pair a polar wind cadence and/or speed sensor with a Garman 910 XT? I have tried a few times now, following the instructions on the garmin site. With no success. Am I doing anything wrong, or does this simply did not work?

    • BartW

      No. Polar W.I.N.D. is a communication “standard”l from Polar and cannot be used by anything else than Polar W.I.N.D. compatible devices. W.I.N.D. devices are EOL (end of life). Garmin (and many others) use ANT so you will need an ANT sensor. Polar (and others) use Bluetooth smart for new developments.

  142. Ryan

    Hi. Sorry if you have commented on the following before. I have the 910xt and the gsc 10. Indoors I know the gsc will measure your speed/distance and cadence. My question is outdoors: wich unit measures speed/distance outdoor – the gps or die gsc? Does the gsc only take over when the gps has lost signal?

  143. Jason

    I just bought the new Garmin cadence magnet-less sensor and am trying to pair it with my Garmin Edge 500. I’ve gotten to the page that says Bike sensor present? and Yes. I tried to Search but it goes back to prior page. I tried Sensor Details and got to page with Sensor Status. But it won’t connect even after I check Cad Sensor. What am I doing wrong?

  144. Don Draginda

    Wow, great info. Just got Vector. I use an Edge 500 and the GSC-10 combo sensor currently. From an earlier post I know the GSC-10 provides better info for cadence only in high RPM, for me, the cadence from Vector will be sufficient. I also know the Edge 500 uses GSC-10 cadence rather than cadence from Vector. I don’t care about indoor speed info and generally ride outdoors in areas with good GPS reception. Are there any benefits to keeping the GSC-10 installed?

  145. sergio T

    good afternoon
    I’m really impressed with the quality of their assessments.
    I wanted to ask you a question
    I have a Garmin 800 and I use it on my bike that has just spining wheel ahead.
    The question is what speed and cadence sensor compatible with garmin, the best price and to allow me to get the two values​​. Assuming that the assembly depends on the context. For example compatible with the Tacx or the BTwin.

    thank you

  146. Wojtek

    As this is an old article, I don’t really expect to get a response, but still it is worth to try. As I need to send back my FR610 for repair, but still want to continue indoor cycling with my Ant+ HR, speed&cadence, I wonder if anyone of you knows a cool&free Windows application that could capture such data. I am not looking for a virtual trainer for 15USD/month, but just a free app that allows me to display&store data when my Garmin will be not at home.

  147. danial

    Hi..i hv a garmin fr620..can i pair it with my cateye strada slim cyclometer on my roadbike? It is a speed-only cyclometer.

    • Generally no, as the FR620 can only pair with ANT+ devices, and within that, just the ANT+ Speed/Cadence sensor. It does not appear that the speed sensor there is ANT+ wireless.

    • danial

      Tks for yr response. If so, can my fr620 still capture the speed and route while riding if i don’t pair it with any ant+ sensor?? I will still use my current cateye sensor but i need the fr620 for the speed data and route taken. Possible?

    • Yup, correct. The FR620 will use GPS when outdoors – so no need at all for a speed sensor in most situations.

  148. Bruno Mosto

    Hi, i have 2 bikes with a cadence/speed sensor each, I want to buy a 920xt garmin…. this watch could reecognize both sensors choosing the bike (bike 1 or bike 2), or i have to syncronice every time i want to change the bike.

    Bruno

    • As long as you have two sensors, you can save them both as separate sensors with the Garmin Forerunner 920XT, no problems at all there. It’ll automatically detect either sensor when you start pedaling.

    • CLAIRE

      I have a 920 and a Giant ANT but it can’t be found. Are you aware of these issues?

  149. Shannon

    Since this is ANT+ and Suunto Ambit 2S supports ANT+, can i assume both products will work fine? 🙂

    • Correct. As always with the Ambit series, it may take a try or dozen to get it to pair to ANT+ sensors. Sticking them right next to the watch for initial pairing is often required. But once paired once, you’re good to go from there on out.

  150. ANA

    I have the Cateye/garmin speed and sensor mounted in two different bikes. I’m trying to use the Garmin 910xt but the Spd/Cad sensor is Not connected. It’s showing Sensor ID “0”. What do I need to do to make the sensor to work Bike2. Do I need to reset everything and start over? Very frustrated… I appreciate any help.
    thanks

    • Pradeep

      hi i am facing the similar issue on my garmin 910xt.Not able to pair the new magnetless speed and cadence sensor.It says speed and cadence sensor connected but the sensor ID is blank.Could you let me know if you found out what was wrong.Thanks.

  151. Kodchakorn

    I have a Timex Cycle Trainer 2.0 GPS and looking for the speed/cadence sensor
    Is Bontrager Interchange ANT+ Combo Sensor can work with ?

    Thank you.

  152. Yup, it’s compatible here/there.

  153. Carl

    I recently purchased the gsc 10 and am having trouble pairing it with my powertap pro t… It my first attempt using any of these other than using the powertap for heart rate which it works just fine. Any suggestions would be greatly appreciated.

  154. Joel

    I have an old Minoura MAG 850 & and a even older TACX Cycletrack Mag trainer. I want to get a speed/cadence sensor so I can hopefully train with ZWIFT. Any suggestions? Or am I out of luck and need to get a new trainer?

  155. Pots

    I’ve recently upgraded from a Garmin Edge 305 to a Garmin 500 Bundle. I’m trying to use my previous ANT+ Bike Speed/Cadence Sensor on my commuter bike and my new ANT+ Bike Speed/Cadence Sensor on my road bike. I don’t get any speed or distance reading on my 500 for my commuter bike setup. I’ve physically remove the ANT+ Bike Speed/Cadence Sensor from my commuter bike the speed and distance are properly displayed and seem accurate.

    Advise would be greatly appreciated. Thx

  156. I have read your page already and gotten many information about bike details. I have some information about Recumbent bicycle and Recumbent Bike. I’m trying to use the Garmin 910xt but the Spd/Cad sensor is Not connected. Thanks for shearing this page.

  157. Ricardo

    Hi, very good post!
    I am new to those wireless technologies in the bike. I still use a bike computer with wires for speed and cadence. But it is gettin old and sometimes it stops working in the middle of the ride and that makes me really mad!

    I am currently looking for a new computer and there are many different options available. And I will also use it for running.
    But I find it hard to get one to be used in the bike and in the wrist. I mean, the Garnin 310XT or the Suunt Ambit for example are very good for bike and running (swimming also) but I don´t want to keep looking at my wrist to see speed and cadence while I´m on the bike.
    also I have two main questions:
    1- Which receiver would you suggest to use for running and cycling that can be easily taken of from the wrist and put in the handlebar of the bike?
    2- If there is no good option for the question 1, than the solution would be to use a watch and a cycle computer. Can an ANT+ transmitter (HR, Cadence) be paired at the same time to 2 different receivers (watch and bike computer)?

    thanks for the helpful post!
    Ricardo

  158. Bruno Kolovrat

    Hi Ray,

    thanks for these informative and through reviews. Thumbs up!

    I recently bought the Forerunner 920xt and now I am looking for a speed/cadence sensor. I’ve read both of your posts, this one about the Garmin GSC 10 combo or the new magnet-less speed and cadence sensor, reviewed here link to dcrainmaker.com. The price for the GSC 10 is almost the half of the new ones.
    Also, how relievable is the GPS speed sensor on the 920xt since I will be riding 99% of the times outdoors. If the reliability is good then I could just go for the new magnet-less cadence sensor only?

    I’ve been through all the comments here but I couldn’t find any related answers. I apologize though if there is some but I missed them.

    Thanks a lot!

    Bruno

  159. Mauricio Solis

    Any comments regarding the Giant RideSense? I just got a 2016 Defy Advanced Pro 2 and it comes with this, is it worth to use it? I’m planning on getting a Garmin 520 bundle which comes with the cadence sensor, so should I just stick with the garmin unit and remove the ridesense? Any apps that will connect directly to this ridesense or definitely need a garmin u other units to track it? Thanks

  160. albert

    What happen if i wanted to wash my bike? Should i take the sensor off first? or can i wash it without ejecting it? tks

  161. dan

    Thank you for the informative article &comments. I recently purchased a tadpole trike and have a Garmin 405cx paired with a gsc 10 unit. I do not have the speed sensor set up because cranks and wheels are separated and I’m fine with that because I am using it for cadence training. My problem is, the cadence is displaying at 1/2 its actual value (ie I am pedaling at 90, but the unit is displaying a cadence of 45). Any suggestions?

  162. Mind

    Hi
    I am using a Wahoo Blue SC speed/cadence sensor with an Edge 520 (also own FR305 for running and edge 500 for mtb); I have never had a problem with a Garmin device.

    I am getting ghost (error) speeds very often with the wahoo sensor [which are killing my videos].

    I have been contacting their customer support and I have received some emails back but I suspect that, no matter what they say; they are still behind Garmin in terms of quality and reliability. They adviced to do the trivial: replace battery and get sensor closer to magnet; did that and still same results

    I will be ditching the wahoo sensor and will be buying a Garmin speed / cadence sensor. I need a stable and reliable speed sensor [to be installed in look 695].

    Do you recommend the Garmin magnet less sensors or the bullet proof [though bulky] GSC 10?

    Thank you

  163. John B

    Hello Ray,

    Excellent site, please keep up the great work!

    I have been doing some aerodynamic testing on bicycles and logging the speed through a speed and cadence sensor. One interesting thing is that the old Garmin GSC 10 unit sends a signal at every magnet sensing event, whereas the Bontrager DuoTrap / Motorola style send an update every second.

    The ANT+ protocol for speed/cadence meters give the time of the last event and cumulative revolutions. So at 25mph there will often be about 4-5 updates on the Garmin unit, there will be 1 on the Bontrager. The speed is calculated with the equation:

    speed = change in wheel revolutions x wheel circumference / change in time

    At constant speed, both should be equally accurate, however for fine measurements while accelerating or decelerating, the old Garmin GSC 10 gives a better data read out. The quicker update also leads to a nicer real time display.

    As Garmin has changed there speed detection method to the accelerometer style which seems less accurate, it would be interesting to know if anyone is still making an ANT+ magnet sensor that updates on a per event cycle rather than the constant 1hz.

  164. Ajahnae Hinley

    Hi there,
    I have the Suunto Ambit 3 watch and I understand many of the cadence /speed sensors aren’t compatible. Are there any wireless ones compatible that you’ve come across since the release of the Ambit3? I want to use on my bike for indoor use and of course outdoor (to the extent the watch doesn’t have a feature).

  165. Angela

    Hi I’m looking at purchasing a refurbished Garmin 500. It comes with GSC 10speed. Will this work with 11speed?? I have the Giant Propel Advance bike which already has in built in speed/cadence sensor but can’t see anywhere if this is compatible with Garmin 500. Thanks in advance for help.

  166. Marcelo Vaccari

    Hello Ray. Great info, as usual.
    I’m looking into buying a Wahoo Elemnt Bolt, but the bundle which includes rpm/cadence/hr sensors are way too much for my pocket right now. Here in Brazil, we pay over exceeded taxes. So I’m looking into others brand sensors and would like to ask you if there is a significant difference in quality comparing to the wahoo sensors when paired to the Bolt. I found these ones link to bikepointsc.com.br from Bryton (they sell for around 100U$ here in Brazil, while the Wahoo is double that). And I already own a ANT+ heart monitor from Garmin.

  167. CJ

    Hey Ray! I’m not sure if you even see new comments on way old posts like this but…

    Any thoughts to a “alternative sensor tech” post?

    There are a lot of companies offering inexpensive ANT+/BLE sensors and it’d make an interesting article. I’ve tested about a dozen of them and they all work great, at a fraction of the price of the big brands.

    Like Trek’s DuoTrap, Giant offers the “RideSense 2.0” which integrates cleanly into most current Giant frames. (older RideSense 1.0 for older frames).

    The Meilan C1 looks like a Magene pod but has a button to toggle between CAD/SPD, so it can be configured for either. (ANT+/BLE)

    CooSpo offers a combo pod that does SPD/CAD, also ANT+/BLE.