doldonics

Kickr Vibration issue not the bearings in my case - but solved

As with everyone else that appears to have vibration issues with their kickr, I replaced the bearings on the flywheel. The vibration went away for about 4 rides, then started coming back. So I took it apart again.
The first time I took it apart, I noticed iron dust in the area that is inside the flywheel. I could not figure out where it came from, but I cleaned it. When I took it apart again, this time there was more iron dust. WTH? So I took a good look and found out that the wavy spring steel washer they use to keep the axial preload had eaten into the flywheel at the flywheel/shaft interface. This was allowing the flywheel to move in/out axially about 1 mm. Now we have a spring/mass system, and depending on the forcing function (the pedaling speed) the vibration was different at different cadences. I ended up making several steel shims/washers with an ID of 11/16" and OD of .9" in thicknesses of .03", .04", and .05". The .04" one did the trick, it allows only a slight axial movement of the flywheel, and lets the spring washer keep the preload correct.

When I purchased the Kickr, i adjusted the belt tension so that it was not as high as the factory. The bearings I took out were not "worn" and were still good, they rolled smoothly even under pressure.

So If/when you decide to replace the bearings, if there is iron dust on the flywheel side, make sure to check the axial play of the flywheel. You can see the wear on the spring washer also, it will have 3 shiny spots on it.

- Doldonics

p.s. I have pics but am not allowed to post them yet....

jaxgtr

Did you send this info to Wahoo?

doldonics

I have contacted Wahoo to see if I can get a replacement flywheel. I included pictures of the issue, it is pretty clear.

unterhausen

If you post your pictures to an album in your gallery, we can rescue them for you and put them in this thread. I would like to see them

doldonics

I just posted them to the main gallery, do you see them? I could also send them directly to you if you would please put them into this post.

I think that this issue is common. If the bearing on the flywheel side starts to have any rolling resistance, the spring washer will have no choice but to either rub against the flywheel or the bearing. Since the bearing is hardened, it will not wear, unlike the flywheel.

Danhedonia

I'd also like to follow up with Wahoo. I have some dust collecting, and TBH I am not going to attempt to fix it myself and wouldn't mind shipping it back for them to address (during summer, of course), but they should know.

unterhausen

Pictures, thanks for posting

Danhedonia

Huge thanks to unterhausen . I opened a ticket today, hopefully there will be a dialogue with Wahoo with good results.

unterhausen

So there isn't enough preload. Were those silver washers stacked next to the wavy washer?

doldonics

No, the silver washers are the ones I made, it was difficult to measure the exact thickness I needed so I made a bunch with different thicknesses and tested to see which was the correct one. There was only the spring washer in the Kickr.

I contacted Wahoo, they told me that they do not sell the flywheel, but they have a "low cost certified replacement program". Not sure how much that is. Right now it is running well again.

Next time I make the shims from Bronze.

HudsonBayCo

Thanks for this! Iv been fighting my V4 Kickr for weeks now and have tried a lot of things, this worked!