Erratic power reading with Kickr Snap

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1

Hi,
My Kickr Snap is showing Watt output fluctuating wildly by about 20-30W despite keeping steady even pedalling. Trainer was working fine but only started doing it last week - I have performed advanced and normal spindown but this hasn’t helped. It happens in Ride mode and on Clear Workout but the pre-progammed workouts seem to be working perfectly with normal power readings?
Can you help please?

1 Like
2

Did you do the recent firmware update? If so, did this problem start after the update and also, did you do a power-cycle of the snap after the update (unplug from wall).  I also have a Snap and haven’t quite got the nerve up yet to upgrade the firmware.

3

Yes, you’ve hit the nail on the head - problem started first ride after updating firmware, I thought that might be the problem but I would have assumed it should have been heavily tested to avoid something as fundamental and obvious in the performance.  I have it plugged but no joy.

frustrating!

4

There are some extensive discussions about this problem in other threads. Your 20-30 watt fluctuation isn’t nearly as bad as what some people are reporting. Are you using 3 sec smoothing? Maybe this is how IRL power meters work. The new firmware does have some big advantages, such as preventing power drops on descents. I will probably upgrade soon. It is possible to revert back to old firmware. You can find how to revert back in the other theads. Good luck!

5

I have also been seeing the same power fluctuations of around 20-30W on my kickr snap after doing the latest firmware upgrade recently.  I believe this is a wahoo problem because I am seeing the same fluctuations in power readings when using the wahoo kickr app.  Nothing else has changed in my setup except the firmware update.  The 3 sec smoothing helps when riding in zwift but my power numbers still are changing a lot more than before.

6

Response from Wahoo Support on this as follows:

No acknowledgment there is anything wrong with the firmware but they have provided advice on how to revert back to the old version!

Hello Kieran-

I am sorry you are having this issue with your Snap. Please try the following steps.

Setup

Pump up the tire to the sidewall recommended tire pressure.
Adjust the roller until initial contact with the tire. After initial contact, turn the blue knob 2 full turns and check for excessive tire slippage(some slippage is ok). If the tire is slipping too much turn the roller by a ¼ turn until slippage is reduced. It is VERY important that the roller tension is not excessively tight or loose.

(Basic Spindown)

The spindown time should fall between 12-15 seconds (ish). Spindown times outside of this range do not necessarily indicate a problem. If power readings seem off, try to get a spindown time within this range by tightening or loosening the roller. Make sure sidewall recommended tire pressure is being used. It is important to get a reasonable spindown time before performing an advanced spindown.

Advanced Spindown Tips:

In the Wahoo Fitness App, select Sensors->Select your KICKR Snap->Spindown->Perform Advanced Spindown

Complete the 3 minute “Warm Up” phase riding over 10 mph.

Perform 2 back to back spindowns as instructed and wait for results.

The second spindown time(with the brake on) for an Advanced Spindown should be 5-7 seconds (ish)

If you would still like to change back to 2.0.28, please use these steps.

Android Steps

  1. Open the Wahoo Utilities app app.
  2. Make sure the Wahoo device is powered on.
  3. Click on the Wahoo device when it pops up.
  4. Wait for the Wahoo Device to connect, once connected tap the grey icon of the device with the Bluetooth emblem in it 10 times to bring up the firmware update list. It will show what firmware is current, choose the latest firmware next to that update in the listor the one that is (recommended).
  5. Allow the update to finish and try and reconnect the device to the Wahoo Fitness app when done.
  6. Return to the Wahoo Fitness app, repair the sensor in the sensor settings and save the sensor to the proper workout profiles.
  7. Return to the main wahoo fitness screen, select the proper workout profile and start your workout!

IOS Steps

  1. Open the Wahoo Fitness app.
  2. Click the sensors icon on the bottom left side of the app.
  3. Click On the device if it is saved, find a new sensor if it is not saved.
  4. Click on the Wahoo device when it appears and wait for it to connect.
  5. Click the grey device icon with the Bluetooth emblem in it 5 times to bring you to the firmware update screen.
  6. Click on the recommended update or the downgrade to the current update you are using.
  7. Once complete, go back to the sensors page,save sensor to the proper profiles.
  8. Return to the main screen, select workout, and start your workout!

Please let me know if you have any other questions.

Thanks,

Dub

7

They have released a new update to smooth it out. But it’s still more erratic than before. Not a fan.

Anyone know the upside to this update(s)?

8

Hello everyone…as a bike shop owner that is trying to train clients and encourage them to join the Zwift community, it is very frustrating to see such power fluctuations.  I have tried the spindown, both advanced, and simple.  I’ve unplugged it etc…I really hope Wahoo can fix this issue.