Clunk through pedals on Kickr 18

whyamihere
whyamihere Posts: 7,713
I have raised a support ticket with Wahoo, but asking here as well just in case someone has experienced this.

I'm getting a slight clunk feeling through the pedals. I first noticed it yesterday, which was a 1 hour 50% FTP recovery ride. I wasn't able to investigate it then, but have this evening. What I've found when pushing the pedals by hand is that the clunk seems to occur just after the freehub engages, though not every time. The best description I can give is that it feels like the freehub engages and then the freehub body moves slightly against the flywheel. Unfortunately, this is pretty much impossible to show on photo/video.

As an example, if you had a bike with a screw on freewheel, you would screw it on most of the way, then you could give a kick down on the pedals to fully engage the threads, and you may feel a small clunk as the thread fully engages. This feels like that, but is repeatable, so if it is a similar cause, then something is moving in and out of engagement.

So, any ideas? Has anyone stripped one of these down sufficiently to see how the freehub engages with the flywheel?