Been fighting this/these (see below) problems for at least a year now on a Gen2 KICKR. Though I haven’t solved my problems, I have been posting the info below whenever I read similar posts in case it helps someone else.
After hours of troubleshooting, using various aps to read/control the KICKR, reading power on-the-bike powermeters instead of the KICKR, here is where things stand, by no means are these the final answers and they may be unique to my KICKR. I have replaced the PC board once under warranty but Wahoo is sure my problem is signal interference, which, if you read the details, is highly unlikely.
The KICKR is sensitive to light shining onto the photosensor. The photosensor is what determines flywheel speed and, consequently, watts so it’s important not to give it any interference. A garage door opening during a bright sunny day will produce this problem fairly reliably, though not universally. Positioning your setup so the flywheel is not bathed in sunlight intermittently should help. Others have put a piece of tape on the plastic shield covering the electronics and folded it in such a way that it covers the flywheel slightly.
The KICKR has a thermosensor that through some algorithm alters the wattage it reports to compensate for temperature. Once your flywheel is up to speed, mostof those watts you’re generating go to heat. If you do a spindown using the Wahoo iphone Ap, you can see the internal temperature.
a) My KICKR drifts to report higher watts than an external SRM after about an hour of FTP-ish level pedaling. It’s most noticeable with longer intervals than short VO2/anaerobic ones. The problem seems to also be getting more common.
b) Mine also appears to reach a “braking point” when resistance just goes through the floor, and any pedaling produces unbelievably high watts. This is similar to that described in the post above. Even trying to hold just 100W, the KICKR will read close to 200W (over either ANT+ on a PC running TrainerRoad or BT on an iphone running TrainerRoad or the Wahoo Ap) If I do a spindown during one of these “braking point” events, I’ll get crazy temperature readings, like -350 Farenheit! Eventually, presumably as the unit cools, resistance will return back to relatively normal levels.
My conclusions are that the light sensitivity can be dealt with with some judicious positioning of the KICKR. The temperature problem may be a design flaw, or just a bad unit in my case. I will try a dedicated fan on the KICKR and am still in touch with Wahoo customer support since the problem doesn’t seem to affect all users.