An update on the 4iiii Precision Power Meter


Quick update/note – July 27th, 2015: Many of you have asked when my review of the 4iiii Precision Power Meter will be released.  While I received a number of test units back this spring, I’ve run into a bug/issue that 4iiii is working to fix.  Said bug impacts my ability to get any accurate data out of the unit.  Not all users have this problem, but rather it appears to be dependent on my specific pedaling style.  As a result, I’m waiting for the bug to be addressed (which 4iiii says they’re working on) before spending the time gathering data for the review (since today’s data isn’t useful).  As a result I’ve tabled the review until that point and are working on other power meter reviews.  Hopefully they’re able to sort it out.

It’s been just under four months since 4iiii announced their sub-$400 power meter, Precision.  You’ll remember when I took it for a test ride back at Interbike, giving it a bit of a first look on their prototype platform.

Since then they’ve been hard at work attempting to hit a self-imposed ‘ship pre-orders by December 10th, 2014’ date, and now that said date has passed many of you are looking for a bit of an update.  While 4iiii themselves have indeed provided an e-mail update a few weeks back, I figured I’d spend some time here at CES to catch-up with them and get a quick run through of where they stand and the path forward.

The Final Design:


The first thing you’ll notice is that they’ve refined the exterior design of the unit.  Obviously, as I stated back in September this was expected since then it just looked like a slightly smoothed brick.  You can see the prototype below, along with the final unit to the left.

You’ll notice that it has two ‘wings’ on the left/right sides, these are for use during the installation phase where you’re attaching it to the crank arm (or, your bike shop if you choose that route).  Then the battery cover has been tweaked to be a bit easier to remove and put back on.  But still the same CR2032 battery as always.


Next we’ve got the much refined calibration kit.  You’ll remember back to the installation process I did during the first install – it was a bit…special.  Now it looks all ‘consumerized’ and high tech.

First up is attaching the pods to your crank arms via the epoxy substance I described in my September post.

To do so, you’ll use this tiny little tool (that doubles as a bottle opener) and the included band:


By rotating the tool upwards against the crank, it locks the pod in place with the epoxy:


Then will come the calibration portion, which is using the components seen below.


What you’ve got is basically two machined pieces.  The first is the long piece that you’ll attach where your pedals normally screw into on the crank arm.  It has a side marked ‘L’ for left, and then the other side is for the right crank arm.  This is only temporarily used, but it allows them to measure how your crank arm reacts to force.

In order to get those forces you’ll hook a minimum 10 pound weight to the bottom of the metal piece, where the little hook is.  You’re welcome to use more weight (it would technically improve results).  This can be a dumbbell you have around the house, or anything else that you can attach via string.  Then, with the calibration pole screwed into your pedals, and the pod exactly as shown below, you’ll weigh that weight three times.

If you look at the two photos below you’ll see the weight is moved between two of the three positions.  By having the unit ‘weigh’ your weight at three different positions, they can determine the exact weight as well as the force exerted.  Now it’s important to understand that this isn’t like a ‘normal’ power meter weight calibration where the weight of the hanging weight must be exactly known down to the millionth degree.

In this case, the exact weight is irrelevant, because they can determine it by weighing it at three different places (two of which are shown below, the third is just a bit further to the other side).



As noted previously, you can setup the unit in a left-only crank arm configuration (kinda like Stages Power), a right-only configuration, or a complete dual configuration (kinda like Vector power).  Totally up to you and how much you want to spend.

The State of Shipping:


Despite having the packaging complete, as seen above, they missed their planned early bird date primarily to complete further testing.  The majority of recent time has been spent putting in serious miles on the final production versions.  One of the components that’s currently holding up shipping at the moment though is FCC certification of the communication components being used.  For a product such as this using mostly well used components, these particular certifications are more a formality than something considered to be a roadblock.

At present they’re estimating they’ll have a final production unit on it’s way to me within 1-2 weeks for me to start testing.  They expect shipping to occur in that same ballpark, so probably safe to say by the end of the month at worst – assuming no issues arise.

Note that they’ll be rolling it out by crank type.  So when your unit will ship will vary by them validating/testing your crank arm.  They’ll be publishing  schedule of that along with some communication to those who have ordered to gather crank type information to ensure your cranks are compatible when the unit is shipped to you.

With that – looking forward to getting a unit in hand and seeing how things shake out as part of my usual and full in-depth review process.  Stay tuned!

Welcome to CES 2015! Don’t forget to check out all my CES 2015 coverage, as well as my continual updates throughout the day on Twitter.  It’s gonna be a crazy busy week!


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  1. David Manley

    Disappointing about the carbon cranks but still looks promising. Hope the UK price is not the £400 = $400 usual

    • Phill Smith

      I got mine in the uk for £288 for left side only with calibration kit and shipping

    • Pawel

      Hi Phil, how did you get the device in the UK? Did you order directly from the website? If so, have you enquired about warranty? Where/How could you have it serviced if needed?

    • Phill Smith

      Yeah I just got it from the website around late October time, think it was $50 as the cheapest shipping option so just over £30 and I didn’t bother checking about warranty/ servicing haha. I’d just email them to see what can be done if and when.

    • Lee Sutton

      Don’t forget you’ll need to add 4% import duty on that then 20% VAT on the total so about £70.

  2. Kyle

    Hope everyone you know in Paris is safe. Know this isnt the most appropriate place for it, but it’s the only one I have access to.

  3. Tosin

    That looks amazing. Questions then are what happens if a few years go by and you want to put it on another bike, is that a possibility to remove the epoxy? I guess it would be the same question for Stages.

  4. Colin

    Will you test it on carbon cranks anyways? Carbon vs. aluminum. Are they more worried about the pod falling off the crank or providing inaccurate readings?

    • KenZ

      Likely working on any negative effects that the adhesive has on the CF composite. Remember: CF has a resin holding it together,which is basically a polymer (plastic). The adhesive will have some amount of solvent in it, and that could POSSIBLY have a negative effect on the cranks. Kinda like how you’re not supposed to put stickers (unless designed for helmets specifically) on helmets lest you degrade the shell material.

    • Colin

      I did think of the resin but only on an adhesion aspect. I didn’t think about the degradation of the epoxy. That is a good point and I hope they release something soon. I purchased one through clever training.

  5. Emil

    Thanks for the update!
    One thing I’ve been trying to find out is how the unit works with alloy crank arms that are milled out/concave on the inside. One example is the Campagnolo Athena crank that is listed as compatible on the 4iiii website.

  6. Brent

    Any news on the Viva Mini heart rate monitor?

    • Right now they’re focused on getting Precision out the door. While some development is continuing to go forward on the pods, the official date is Spring/Summer.

    • Havelaar

      What’s the world record for delays between initially announced release date and actual shipping of this type of product (heart rate sensor)? Because the might actually manage to break it.
      I was very patient with 4iiii. But enough is enough. Congrats you just lost a costumer for good.

    • As noted before, they found in testing that the previous optical sensor wasn’t working well upon integration (it sucked), and had to change vendors. Said process meant they more or less had to start from scratch.

      Now, I can see being mad at them for not communicating about it (no doubt, it was poor), but I just fundamentally don’t get being made at companies for doing the right thing and not releasing a crap product.

    • Havelaar

      It seems that in the world of ever shortening product cycles we somehow forgot that not releasing crap products should be a matter of course. But that’s another topic.

      The question is why making the initial product and release date announcement (and also the subsequent one, which has not been met either) before even testing the maturity of the optical sensor, which is the very heart of the product.

      And by the way, a year ago they also announced two other pods (FYiiii Notifier and SideKiiiick GPS) to be shipped in April/May 2014. Where have they gone? Also a sensor problem?

    • No, those are trying to decide whether or not there’s still a market for those products, either as a standalone or rebranded effort. I do definitely agree, they should be communicating more frequently.

      I had a good chat with them about it 2-3 nights ago (communications), so I think you’ll see some progress there (I hope).

    • chukko

      They can hardly beat SRM 8 – it was first planned for Spring 2014, then December 2014 and it is still not out :)

    • Technically speaking the SRM PC8 was simmering for much earlier than that…

    • Matt

      Don’t forget about the Garmin Vector. That took forever to come out.

  7. Stefano

    I have Look’s Zed2 cranks, and have been back and forth on various PM to purchase, from Vectors to SRM. But since i want to keep the cranks, SRM and QUARK are out. Almost pulled the trigger on a Vector S, but every time, i end up going back to 4iii.
    Wish they made the update, so i can buy one.

  8. Patrick

    Ha, I was losing it at the part about using a dumbbell from around the house (due to weights being less than standardized so you can buy weights for a decent price). Then I finally read far enough to see that it doesn’t matter.

    Thanks for the update! I’m excited to see where this takes the PM world!

  9. Drew W

    This is the one thing I was waiting to see out of all the CES coverage. I’m still excited about this device as the most affordable power option out there. I’m eagerly waiting on people to get their hands on the units & get them installed so I can get some solid guinea pig data & reviews. haha

    And personally, I liked the original wedge shaped design better than the new design.

  10. Steven Shaw

    Should this work with polar v800 (and upcoming v650).

  11. Steven Shaw

    I presume those ‘wings’ could be removed once installed? They look as though they are just there to connect some rubber bands or similar to provide pressure whilst the glue dries.

    They do look a bit rubbish, and agree the original looked better.

    • Simon S.

      Apparently the ‘wings’ are permanent on this iteration. I suggested a future iteration having the wings as part of a removable plastic collar…4iiii said it’s a ‘good idea’ and they’d investigate the feasibility. In the meantime, they could probably be carefully removed with a hacksaw blade and polish the cut with some fine sandpaper (once the epoxy has cured of course).

  12. Kimaes

    I asked for sworks cranks and doesnt works for carbón cranks yet

  13. Kimaes

    I asked for sworks cranks and doesnt works for carbón cranks yet

  14. ThomasR

    I ordered one from Clever Training back in November, haven’t heard anything since. I assume they will start asking the same crank type questions or will this be handled by 4iiii? I have a pair of Shimano 6800’s, btw.

  15. Simon S.

    Something about the calibration setup in the photos just doesn’t make any sense at all. I think showing the sensor in the centre of the machined piece is a red herring. By calibration time it should be epoxied onto the crank arm & nowhere near close enough to the pedal spindle to make the geometry in the photos work.

    • Not quite sure what you’re referring to. The calibration kit integrates a pod with similar plastics to Precision, but they’re not quite the same. The calibration kit pod knows what the strain characteristics of the load cell looks like, so it can tell the installed Precision how much torque it should be seeing from the weight. Precision then uses that to determine its calibration factors.

    • Zan

      The sensor is mounted on the bike during calibration. The pod you see in the machined piece is just part of the calibration device.

      Think of it this way. If you hold a stick out from your body parallel to the ground. And then hang a weight from the stick right next to your hand. And then hang the same weight from the end of the stick, it will be much harder to hold the stick when the weight is mounted from a further distance. So the same weight at different distances creates different amounts of torque. By measuring the ratios of the torque created by the same weight at different distances, you can accurately calculate the weight. Once the weight is known, the calibration process is essentially the same as with other power meters. This method of calculating the weight essentially just allows you to bypass the step of having to find a weight that is known to great accuracy to hang from the crank (something most people don’t have at home).

    • Fran

      I was also confused, y the fact that both pods, (the power meter itself and the calibration kit pod) are identical, it even has the “wings”, which makes no sense. I imagine they are trying to cut costs, but it makes it all lack polish and look a bit too rushed IMO

    • Simon S.

      Thanks…it wasn’t obvious from the article that we were looking at a calibration pod (not the power pod) in the machined piece. It all makes sense now.

    • I think you missed the line of text in between the two photos that said “Then will come the calibration portion, which is using the components seen below.”

    • Simon S.


  16. David Tucker

    I really don’t like that this becomes a permanent part of the bike. Surely there has to be a better way to mount it that would allow it to be moved? While the price isn’t bad, its still expensive for something that can’t be removed.

    • Tim

      it’s really not a permanent part of the bike, at least only in as much as many other meters. You can swap the crank arm to another bike (as long as the other bike supports that crankset).

      Same as P2M, Quarq, Stages…

      Similarly with PowerTap you can swap wheels as long as the wheelset and gearing is compatible.

      Of course vectors or Brim Brothers may be a little easier to go between bikes, I’d argue the pedal swap (given what I’ve read on installation sensitivities) isn’t any easier than a crank arm.

  17. Nigel Van de Velde

    Thanks for the update on 4iiii!

    Did they mention something about Europe based distributors? Customs in Belgium can be quite unpleasant if you are importing from outside Europe….

  18. Tim

    I’ll be interested in a better way to check crank compatibility. I don’t see FSA Gossamer listed and the SRAM Apex on my wife’s bike also missing (both of these appear to be rightfully missing by my review, neither has a totally flat on the backside)…

    Ok, both cheap crank sets that should be upgraded, but they’re what I had to look at :)

  19. masanori iwamoto

    How do we know the exact place the unit to be on a crank arm? The prototype had a sort of the scale jig to get the proper location right? Or it neither matter because the kit hook has also a strain sensor and got factory calibrated and the installed unit learn relative slope factor from the kit?

    I think this is great not only for the easy installation but also it colud allowed some fine tuning by advanced users.

  20. masanori iwamoto

    How do we know the exact place the unit to be on a crank arm? The prototype had a sort of the scale jig to get the proper location right? Or it neither matter because the kit hook has also a strain sensor and got factory calibrated and the installed unit learn relative slope factor from the kit?

    I think this is great not only for the easy installation but also for potentials which colud allow doing some fine tuning by advanced users.

  21. Marvin O

    This is very exciting!

  22. Jake

    I don’t understand how the calibration works. Once the device is epoxied to the crank arm, how can you attach it inside the S shaped piece? What am I missing?

    • Zan

      The pod in the S shaped device is not the power meter. It’s a separate pod that is part of the calibration tool. There’s a more in depth explanation in an earlier comment.

  23. Sal

    Hey Ray
    Will you have a look at Bragi’s “The Dash” at CES?
    That Kickstarter project seems to be ready for release.

  24. Cloggsy

    Really cool! Just hope we get a UK stockist, or they’ll mail stuff over to the UK for us (at current exchange rates) :lol:

    • Lee Sutton

      Pinpoint Consumer Electronics is going to be the UK distributor. I’ve been in contact with Rod (rod@pinpointce.co.uk ) there and he’s good at replying. They should have a production unit at the London Bike Show next month.

    • Lee Sutton

      Pinpoint Consumer Electronics is going to be the UK distributor. I’ve been in contact with Rod there and he’s good at replying. They should have a production unit at the London Bike Show next month.

    • Nick

      Weird choice, never heard of them, their website is virtually non existent. I’d have thought this would have been a good choice for one of the more mainstream distributors.

  25. Matthias

    Too bad this cannot be attached to my Rotor crank :(

  26. ModernCyclist

    I’m one of the many anxiously awaiting pre-order customers. I know they have been working hard to get this power meter out to consumers but they have done a very poor job of keeping their pre-order customers informed on their order status. First early December deadline came and went without a peep. Then we got an email requesting crank-set model, shipping before end of December. Then end of December deadline came and went with no status update.

    I’m still looking forward to getting this unit on my bike but they should do a better job communicating with their customers.

    • They sent a general status update on December 12th to all pre-order customers from their site (as well as posted it on Facebook and other social media sites). I’d double-check your Junk E-mail folder.

    • ModernCyclist

      Your right Ray. The statement below was sent two days past the shipping date on the 12th and the request for crankset information was sent on Nov. 28th to correct my timeline above. With that being said, I still think if you’re going to miss a deadline, you should advise pre-order customers before or on the day of. The last “end of December” deadline has long past and before your post, I don’t believe anyone received a order status update. Not trying to nitpick, but if you happen to chat with the 4iiii team again, let them know they should reach out to their pre-order customers.

      Email of December 28th:
      “Further to Emma’s correspondence in regards to your crank type, we are sorry to say that we didn’t hit the planned December 10th shipping date, but we aren’t far off the mark.

      First units will start shipping at the end of December. Our commitment continues to get Precision on your bike this spring. We are testing with local Beta users to finalize the last details.

      We will be shipping aluminum-compatible Precisions starting with crank manufacturer and model number. The compatibility list will be updated on the website as final testing is completed on the cranks.
      Carbon-compatible Precision will be available when the full suite of testing and calibration is done on a manufacturer and model number basis. In the meantime, do not install an aluminum-compatible Precision on a carbon crank, as this will void the warranty.

      Since we announced at Interbike in September, the design of the unit has been further improved, making it easier to install and now, the unit is even smaller to accommodate tighter clearances on more bikes. Here’s a sneak peak at Precision.”

    • I don’t disagree with you in general. One thing that Recon has done (though, I think lately fallen off the boat on) is to establish a known cadence for communications. i.e. they’ll provide monthly update, or similar. I think something like that is probably a worthy approach.

  27. ricky

    The product looks much better now. Just the wings that should be able to remove arter it been attached.
    Im also wonderingwhats happening got the mail sent them my carbon cranks picture. Heard nothing.
    Hopefully a Little better Communication with us preorders people that would be Nice.
    Im sure most of us realized that we perhaps shouldnt get them to christmas, but atkeast let us know whats going on from time to time.
    Keep up the good work and hopefully perhaps my cranks are compatible.

  28. John

    I wish they stayed with the earlier battery cover. If it is anything like the Stages, you will be going through them like hot cakes.

  29. Bryan

    Thanks for the update. Much appreciated!

  30. ChrisK

    A few hours ago 4iiii posted on Facebook that they will be posting updates on the Precision starting next Friday.

  31. Mike T

    I have a cyclocross bike that doesn’t have enough space to put a pod on the non-drive side. Will I be able to put it on the drive side only on my Ultegra compact 6800 cranks?

    I’m assuming the pod will be between the crank arm and chainring so spacing to the bike is not an issue. I see on their website that the 6800 has clearance on both sides.

    I have a powertap that works great but I switch between road and CX tires quite a bit so I’m tired of changing tires. During race season, I have a tubular wheelset and really want to gather data during my races. Having a crank based PM will be a quick wheel change instead.

  32. Mike T

    I emailed 4iiii and they said that the Precision module is not side specific and it will figure out which side it is on during the installation.

    So I can install the module on the drive side only. Can’t wait for this to be out in the world and get reviewed by Ray.

  33. Netwalker000

    I’ve asked on clever training for the compatibility-order thing and they emailed me that they will not ask for the type of crank and if I have a crankset that isn’t compatible to the precision pm, I should cancel my order.

  34. Dominik

    I’ve asked on clever training for the compatibility-order thing and they emailed me that they will not ask for the type of crank and if I have a crankset that isn’t compatible to the precision pm, I should cancel my order.

  35. Dominik

    I’ve asked on clever training for the compatibility-order thing and they emailed me that they will not ask for the type of crank. If I have a crankset that isn’t compatible to the precision pm, I should cancel my order.

  36. Andy

    Waiting for the 4iiii update. Still a 404 error on the page where they said they’ll post it: link to 4iiii.com. I’m getting more and more nervous about this product. I hope that when they do post the update there’s lots of detail around the issues they’re facing and what’s being done to solve them.

  37. ModernCyclist

    They have posted new information on their Facebook page 15 minutes ago. Apparently they have figured out a solution for the installation setback.

  38. chris

    Are there any advantages with ordering through clever training?
    WHy would order through them as opposed to 4iiii directly?


  39. chris

    Even better.

    Now that shipping is presumably just around the corner, I’m starting to get a little excited!

  40. Howard

    Does any know whether this 4iiii precision will work with Cyclemeter iOS app? thanks.

  41. Philip King

    Couple of questions, “water proofness” for MTB use and can the wings be used to additionally secure the pod to the crank with rubber bands rather like the Garmin Edge holders are attached?

    • I believe it’s IPX7, which is more than enough for mountain biking (IPX7 is 1-meter deep for 30 minutes).

      As for the bands, no, keep in mind that’s just for installation. It needs solid/permanent and non-budging contact to get accurate power numbers.

    • Philip King

      Many thanks!

      I was more thinking of a back up in case the epoxy failed, (unsure to whether I’d trust “just” glue to attach a $400 bit a kit to a relatively exposed are of the bike).

  42. Herche

    Any word on why they pulled self installation off of the table yesterday?

  43. Henrik

    How will they cope with overseas orders from Europe then ? I assume they will not offer to pay the shipping and insurance for my cranks to them ? How long would such an exchange take ? I do not necessarily want to wait at least 6 weeks for my cranks…

    • Netwalker000

      And what’s with the costumers that have bought their precision unit over clevertraining?

    • I chatted with CT about this yesterday (Euro orders). They’ve been talking with 4iiii’s, and 4iiii’s doesn’t seem phased about it. Sounds like they’ve got a plan for international folks via CT as well.


  44. Dirk

    This is looking like a painful process for the avid biker. I ordered from Clever training and have heard nothing from them. Clever Training and 4iii need to address these customers ASAP.

    • Hi Dirk-

      They did notify customers though. An e-mail went out this past Thursday (from Clever Training) to all customers who ordered. I’d double check it didn’t get snagged into your Junk items folder, sometimes that happens.


  45. Dave

    They should consider selling the powermeter with a crank, as long they don’t try to benefit from that. After all there’s a reason behind all the interest in this power meter…
    I’d prefer that option. It’s an upgrade for the bike and i wouldn’t have to go trough the pain of sending the box back and forth.

    Do you know if they are planning on this?

    • Lee Sutton

      I emailed them about it and they are considering it. If you have a crank in mind drop them a mail as they’re compiling a list.

    • Michal

      Yeah, they definitely should. I’m really waiting for that option because my current Shimano Hollowtech II crankset (R565) isn’t compatible with Precision. And it should be significantly cheaper than Stages, I believe.

    • Amlien

      They do now, faster than what I expected. Trying my luck and ordered a precision from clevertraining with 10% rainmaker-coupon, plus ultegra 6800 crank = $395 factory installed, calibrated and shipped. Damn thats cheap.

      link to 4iiii.com

  46. Phil Hurst

    I had a pre-order in place for 2 units and calibration kits to be sent to the UK since October 2014. Eventually in February 2015 I got fed up with the delays and then the advice that it wasn’t compatible with carbon cranks, so cancelled the order for both. It’s a great idea, but maybe 4iiii should have sat on it to complete all their testing before coming out with a release date that has been put back and put back. I’ve gone down the Rotor Power route instead now as Stages reportedly has the battery issue and didn’t do a crank arm for my crankset.

  47. Eric Peters

    I Had a similar experience: I had carbon version on order and when I read the message that the carbon version was basically postponed until further notice I cancelled the order. (Will probably get a Vector-S now), As A small benefit I made some profit as a result of the changed dollar/euro conversion rate.

  48. Richard R

    Can anyone confirm if it will cost extra for delivery to europe when I buy a crank arm to have the 4iii installed?

    From the the 4iii website – Shimano will ship crank orders directly to our factory for Precision Install. Please note: Shipping of the crank to us and shipping of the finished crank to you is included.

    But then it says that it will cost 30 bucks or more for delivery… it could really be much simpler! I would like to order through clevertraining too, but as of yet no procedure seems to be in place to get the crank and precision together when ordering from them.

  49. Lee Sutton

    Hi Ray

    Have you had an update on when you might be getting a production unit to test?


  50. Rolf

    Quick question: i checked all your 3 posts on compatibility with FSA Gossamer BB30 crankset as well as the 4iiii website. Nothing showing. I’m not unhappy with my crankset – but I guess I’m also ignorant as I have never even thought about other cranksets. Any sanity saving suggestions from your end towards: ‘replace crankset with xyz because a)… b)… c)..’ or ‘wait till they did their compatibility test’. I’m a Triathlete in my 3rd season, mainly doing 70.3s (guess I’ll never podium in my age group), usually do my 56 miles ~3 hourish on a Shiv Specialized. Thanks a ton for any suggestions.