Rear Derailleur moving inwards

Hi All
I have 2 bikes that i use on my Wahoo Kickr V5 and on both occassions, when putting either of the bikes on the trainer, the rear derailleur moves slightly inwards and my gearing is stuffed.
Anybody else have this problem that may be able to help ??

Maybe include details on what derailleurs you have the problem and number of gears. I have put different bikes with SRAM, Shimano, and Microshift derailleurs onto my Kickr and never saw this. Occasionally I need to fine tune the indexing, most times not. Check your extreme high and low gears if they are fine it’s your indexing.

It may be the spacing of your cassette to the cassette body on the KICKR is slightly off and you need a thin spacer to be installed behind it.

you probably need to re index your gears moving from your bikes wheel to the trainer.

if it is moving inwards - i.e. nearer the trainer - then turn the barrel adjuster clockwise when looking from the rear of the bike. do it a tiny bit (a quarter turn) at a time so you can put it back to how it was if it gets worse.


There’s generally a slight difference in alignment between bike and turbo.

When you sit your bike on the turbo watch the rear mech carefully as you tighten the skewer. You’ll be surprised how much it moves inwards.

You tend to overtighten on the turbo as you fear falling off if you’ve left it too loose.

That or you’re using the wrong spacer, or it’s the wrong way round. Sounds like when I’ve used my bike (130mm dropouts) on my partner’s turbo, when I go to put hers back on it bends the rear triangle/rear mech in when tightening the skewer. I normally notice at this point but can’t imagine it’d be fun to ride if not.