Bad gear on cassette?

Is it possible to have a bad gear on a cassette? I’m on my Kickr with the cassette that came with it. There is a terrible grinding when I hit the 3rd largest gear. It happens when I’m in the smaller and larger chain ring. I have disassembled the cassette and reinstalled it and remounted my bike multiple times. I thought maybe it was the trim, but that seems to be working ok. I would think if it was the trim it would also affect the two largest gears. Just wanted to see if there was anything else I should be looking at doing. I have considered taking the cassette off of my back wheel and using that, but it’s on too tight for me to remove. I’m thinking next step is to buy a new cassette but I don’t want to if I don’t have to.

@NUGirl I had that issue with one gear and took my bike and trainer to the bike shop. In my case I needed a new cassette. I assume the Wahoo cassette is compatible with your bike gears? Also, sometimes it’s a matter of adjusting the deraillur. It always needs adjustment when I go from wheel to trainer or vice-versa even though the cassettes are the same size.

@Petals or @Covi might have some insights.

Few questions?

Are you running the same amount of gears? Are they both 11speed or 10speeds?

Are you running DI2?

What is the gearing on the trainer? Meaning- if they are both 11speed, are they the same size. (11-28, 11-32?)

Both are 11 speed cassettes - looks like my bike came with 11-32 and the trainer is 11-28. Shifting is not DI2. This may seem odd, but when I look down at the cassette, that particular gear looks slightly wider than the others. Maybe I’m imagining it.

I’m deciding if I should try to fix it now or just go back to my old bike. That one only has a 9 speed cassette and I felt like I needed a wider range of gearing options for my workouts. I’m actually kind of wishing I had just stuck with my wheel-on trainer!

Its not a bad cassette. That you are running a different size cassette, you will need to adjust the rear derailleur settings. If you are running an older chain, your chain has stretched based on the 11-28 cassette.
An option would be to swap out the cassettes from your bike to trainer or get a new chain and adjust derailleur settings based on new cassette. I would then keep your old chain with the rear wheel of your bike.

Is it easier to buy a cassette for the trainer that matches the one on the bike? I know it’s extra $, but might be worth the PIA factor of adjusting it?

I’d buy a matching cassette. Both my trainer wheel and race wheel run the same set up and I can make minor adjustments as needed. Plus I don’t have to think about the gearing being different when I ride IRL.

1 Like

that’s what I did too @vivian.a.workman