Wahoo kickr18 Design flaws?

Hello Thasa128,

First of all, due to absolute lack of time, I haven´t posted the outcome of my DIY fix on TR’s forum, which, fortunately, is working perfectly. When I find some time I’ll post details for other TR forum members.

Second, if you have more questions, we can continue this conversation through email. It will be a pleasure to help you out.

Now, answering your questions…

“How do you disassemble thé shaft from thé flying wheel?”
Re: The shaft is pressed into the flywheel. It was taken out by the shop that fabricated the new shaft and, according to them, was no big deal. I took the whole assembly (flywheel + shaft) to the shop and received the same assembly with a new shaft.

“Did you make à 3d of the shaft that I could use for manufacturing ?”

Re: No. The shop that fabricated the shaft took it apart and replicated it’s dimensions with extreme precision.


  • About the shop that fabricated the new shaft: they are specialized in high precision motorsports parts, so they are used to fabricate parts for high demand conditions, like Brazil’s Stock Car Series, Porsche GT3 Cup etc.

  • About the bad shaft (please see attached picture): according to the owner of the shop, the original shaft was made with a low quality steel alloy and the tolerances were all screwed up. The new shaft was fabricated with a much harder alloy (stainless steel) and now the bearings are pressed into the shaft (interference fit) to ISO standards.

  • About the outcome of the DIY fix: it’s been working perfectly so far! Due to lack of time, I have put out only around 10h of use with no issues so far.

  • Would I do anything differently? Yes, but only in a very small detail. Now the bearings are pressed to the shaft, and, because of this, the shaft no longer floats sideways. This setup caused a small misalignment between the belt’s pulley (please see drawing).

As the belt is a v-belt type, it jumped to the next available groove. It’s easy to solve this issue by removing some material from the pulley that’s connected to the shaft, but as everything is working perfectly, I’ll postpone that fix when the belt needs to be replaced.


Ronaldo Spinola