Week in Review–June 5th, 2016


The Week in Review is a collection of both all the goodness I’ve written during the past week around the internet, as well as a small pile of links I found interesting – generally endurance sports related. I’ve often wondered what to do with all of the coolness that people write, and while I share a lot of it on Twitter and Facebook, this is a better forum for sending it on to y’all. Most times these different streams don’t overlap, so be on the lookout at all these places for good stuff!

So with that, let’s get into the action!

DCRainmaker.com posts in the past week:

Here’s all the goodness that ended up on the main page of DCRainmaker.com this past week.

Sunday: Week in Review–May 30th, 2016
Monday: Hands-on with Elite’s new Drivo, Kura, and Rampa trainers
Monday: 5 Random Things I Did This Weekend
Tuesday: Paris 2016 Triathlon Race Report
Friday: The May $600 Gadget Giveaway Winner!

DCR Podcast!

Here’s a handful of the topics discussed in this past week’s podcast:

– A new intro!
– Discussion of Elite’s new trainers
– A well thought through discussion of 24×7 HR overkill
– HR strap chafing, it sucks, and how to fix it
– Fixing Stages calibration issues
– A three year helmet rule
– Where my microphone went to
– Wonky pace issues, and how to fix
– Selecting a cycling speed sensor (and whether it’s worth it)

Listen to the full podcast here on the Podcast player, or just download it directly here.

Stuff that I found interesting around the interwebs:

Here’s a not-so-small smattering of all the random things that I stumbled on while doing my civic duty to find the end of the Internet:

1) Is Amazon going to make a wearable? I’d be pretty darn surprised if they don’t. Listen to what Jeff Bezos had to say though (since his opinion is the one that matters here).

2) Pretty unreal video stabilization on wingsuit: Definitely hit the link up to see the original videos and compare it to the stabilized video.  Though, it almost becomes fake looking.

Stabilization Stress Test from Photon Bandit on Vimeo.

3) Jawbone says they’re note dead yet: Following all the hubbub of last week. Note that they actually said they aren’t leaving the “wearables” market. They didn’t say “fitness trackers”. Meaning, one could easily develop audio wearable products, but still exit the fitness tracker market. Of course, as usual with rumors – where there’s smoke…there’s probably fire.

4) A deeper dive into GoPro as a company: A well written long-form piece by The Verge on GoPro and interview with their CEO, and the challenges that lie ahead.

5) Validity of Wahoo KICKR power accuracy: Interesting study done on KICKR power accuracy. Nothing really surprising here.  Though I thought it was interesting no mention of drive-train loss was noted in the study.  (via Bill Black – Wattage Group)

6) Uber can take your bike home in Amsterdam: Noticed this while up in Amsterdam.  Though, I lacked a bike at the time to take advantage of it.

7) Velon announced live data integration for pro cycling: As a casual reminder – this concept isn’t new. It’s just new again. You’ll remember a few years ago it was totally normal. Then UCI banned it. Then they realized that was stupid, so it’s back allowed again.

8) Triathletes swim in flooded Seine: Seriously, why? All of them were wearing swim caps from the Paris Triathlon held last weekend.  Albeit much of the course is now underwater.  Even ignoring how gross the water is, tons of debris in the river right now.  More on the river in my post tomorrow.

Sports Technology Software/Firmware Updates This Week:

Each week I quickly highlight some of the new firmware, app, software and website service updates that I see go out. If you’re a sports technology company and release an update – shoot me a quick note (just one liners are perfect, or Tweet it at me is even better) and I’ll make mention of it here. If I don’t know about it, I won’t be able to post about it. Sound good?  Oh – and if you want to get a head start on things, this page is a great resource for watching Garmin firmware updates.

Garmin Vivofit Firmware Update: Just for behind the scenes changes in manufacturing

Garmin Vivofit2 Firmware Update: Minor tweaks.

Garmin Fenix3/Tactix Brava/Quatix 3 BETA Firmware Update: Tweaks since last week’s beta firmware. Fenix3HR version here.

Garmin Edge Touring Firmware Update: Single fix for course navigation.

Tip of the week to companies: If you have an RSS feed for updates I can subscribe, like Garmin, Polar, Adidas, Wahoo, and others – it’s nearly 100% how I remember to find these updates.  If you lack that, I likely won’t have your updates in the above.  Plus, users like it too.

Thanks for reading all, have a great weekend!


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  1. Scott Buchanan

    Wing suit stuff….. am lost for words!

  2. Ivan Ivanusic

    Anything about Suunto Spartan Ultra??

    • kyle

      Ray never comments on anything before official, even when its leaks are obvious. Suunto has said themselves June 7th is the embargo date, so id expect Ray will have someone on Tuesday morning

  3. Christopher

    Swimming in the Seine?! Nasty. Just arrived in Paris yesterday for the first time and that looks like a mess to swim in. Not to mention dangerous!! Left Texas flooding to this…hopefully the rest of the week gets better.

  4. David

    The kickr love continues.
    N=1 is not a study.

    Insisting the Kickrs are credible seriously hurts your credibility.

    • And yet plenty of people have no power issues. Also, it might be worth your while to actually read the study and where it did well and didn’t.

    • I do agree however that I wish they had tested more KICKR’s, obtained semi-randomly from around the world. Though, that’s also pretty difficult to achieve.

    • Igor

      I am trying to calculate value of Plenty/Total number of users. Mind helping me with this?

    • Igor

      It is their problem how to get more KICKRS. If they can’t then then they should not publish. Claiming it to be science makes me feel sorry for the states of affairs.

    • The equation can roughly be:

      All trainers produced minus a handful of the same people on Slowtwitch who keep posting over and over again.

      There are a few others not on ST that have had problems no doubt, but I just don’t think it’s a widespread problem. I’ve posted plenty of data from my units over the years, with nobody have issues with those either. I also don’t think many of those complaints have updated firmware with some changes that Wahoo implemented over a year ago.

    • ekutter

      Interesting how the accuracy diminishes significantly below 250 watts. What percentage of users are actually averaging above that? Sure, there are plenty that hit higher watts, but I’d wager to guess at least 90% of hours spent on a kickr are at wattages well below that.

      Comparing both of my kickr’s to my SRM, I usually have about a 5 to 7% discrepancy. My average wattage is usually in the range of 200 to 225. The lower my wattage, the more variable the discrepancy seems to be.

    • A.

      My KICKR discrepancy is 28-29W in 150-450W range, is it really percentage error for all other users?
      I’ve did two tests with two different PM’s, 5-1-5 protocol.


    • Richard Garrett

      I don’t know why they published after only testing one unit.

      Only one KICKR tested means that this entire study should be treated as a singular data point for reference until it can be correlated with the same type tests performed on other KICKRs.

    • Nedim

      Considering the huge discrepancy at different cadences, I wonder if the author has proven inaccuracies with his “CALRIG” or the KICKR. One would assume that, unlike the CALRIG, the KICKR does not know what the cadence is, since there is actual gearing in-between.

      My knowledge of details may be insufficient here. Given that the study does not explain why cadence is important for KICKR, nor does it clearly state which direction the bias is, combined with sample N=1, this does not get a passing grade as “study” from me.

      Now, really, why does the cadence matter?

    • There actually is some validity in testing for cadence levels, though in most cases it won’t matter on a trainer. But in power meters it can be a huge thing.

      Still, it’s something I often test through. The authors also tested at various wattage levels. So I certainly wouldn’t knock him for overachieving in at least looking at whether there were any discrepancies in cadence.

    • Nedim

      Agreed on cadence being relevant to power meters.

      In line with that, looking at the provided chart it does seem that at higher wattage’s the accuracy veers off at different cadence points. It seems to me that what the author really has found is that his “CALRIG” has a lower calibrated range than assumed.

      While there is nothing wrong for testing with different cadences (and a rigorous protocol may even require a spot-check), the old Engineer in me screams “you got it all wrong” to the conclusion the author makes.

      Nevertheless, one observation can be made: The delta between two independently calibrated consumer-grade power-measuring devices is within 2% across a wide range of power.

      From that perspective, the KICKR seems A-OK to me.

  5. leonn


    direct link of podcast is pointing for episode 41, I believe there’s more than 2 weeks with this problem.

  6. James B.

    Were your home or business locations affected by the flooding?

    • Our apartment is good, up 5-6 floors, so would have been waterworld.

      The Cake Studio and DCR Cave (as well as our apartment) all sit on the river. With the Cake Studio/DCR Cave, the DCR Cave is the most susceptible. We don’t know exactly where the water was in relation to the cave, but we think about 1-2ft more and it would have been in the cave. It got super humid in there over the last few days, so we’ve been running dehumidifiers. Luckily, the water level is now down about a foot.

      Finally, we did have another storage cave we use on one of the islands. That is underwater however. We haven’t been allowed in yet, and we aren’t 100% sure what’s in there. It’s more of long-term storage for us, so we think we had a palette or two of boxes. And we believe we have a portable A/C unit. But we’re not 100% sure what else was there. The palettes are plastic sealed, but certainly not against flooding – so they’d likely be a loss. But, could have been much worse for us.

  7. BikeNerd

    Hi Ray,

    Given that you have included the studay about the accuracy of the Kickr in this post, I will ask you the following question. I am using the following setup based on reading up on your posts and listening to the podcast.

    Setup – Wahoo kickr, 4iiii precision and trainer road together. Trainer road is controlling the kickr in erg mode during the workout. Trainer road displays the power from the Kickr while the target power is used to set the resistance on the kickr in erg mode. The 4iiii precision transmits the cadence to TrainerRoad. I also use an iphone to display the power from 4iiii precision to verify the power numbers from the powermeter against the Wahoo Kickr.

    Training – Before starting the training session I do a spindown on the kickr using an iphone and see an offset close to 430-440. I also complete a zero setting on the 4iiii precision using the same iphone. Then I start the workout. After 10 – 15 minutes into the workout (generally after the warm up set) I re-do a spindown on the kickr (offset is generally close to 440). Please note that the power match feature on trainer road is not activated.

    Power results – the power output from the precision stays 30-50 watts lower than the target power throughout the workout. On the other hand the power from the kickr tracks the target poser really well.

    1) Which power data is correct? I have contacted both Wahoo Fitness and 4iiii both say there’s nothing wrong with either of the two devices.
    2) If both devices are indeed working correctly, which device is actually correct?
    3) Is there any way to fix this huge difference in power output between the Kickr and the precision?

    I have also tried to turn on the power match feature on TrainerRoad. However, you can imagine given this huge difference in the power output the resistance on the kickr fluctuates at a very high frequency when power match is turned on and ruins the workout with resistance going from one simulating 350W to 200W in matter of seconds at the same cadence close to 90 – 95 rpm.

    Would really appreciate your insight.


    • With that far off, it’d be hard to know which is correct without a bit more context – at least onwhich one feels right. Obviously, someone is likely wrong unless you have a horribly out of balance left/right leg power output. Doing a roll-down 10-15mins in is where I typically see things settle for the KICKR (and most trainers) as well. So you’re doing that correctly.

      There’s not really an easy way to fix a gap until you know which one is wrong. I’d try and see if you can find a friend with a bike with a power meter on it (preferably not a left-only one) and see if that might help clarify a bit more. Or, a friend with a PowerTap wheel you can stick on your bike.

      I also assume you’ve done zero offsets on the 4iiii unit as well (prior to ride).

    • BikeNerd

      Powertap rear wheel? Can you please elaborate how that will help with the Kickr? Or are you suggesting testing the precision against the powertap rear hub out on the road?

    • Correct, out on the road (or a wheel-on trainer) to narrow down if the 4iiii unit is out of whack.

  8. BikeNerd

    Yes, I do a zero offset on the precision prior to starting the workout.

    I was initially getting offset numbers on the kickr in the upper 500’s. Wahoo fitness was kind enough to change the strain gauge and do a re-calibration and ship the kickr back to me. Now the offset appears in the lower 400’s which per Wahoo Fitness is the correct range. However, that has not impacted the difference in power numbers.

    I have used a Garmin Vector before and my balance used to be closed to 48-52 with the left leg being weaker. So I can undertand upto a 5-10% difference with a left only powermeter. But a 25% variation (50 W variation at a target power of 200W) seems highly unlikely.