SRAM Transmission (on 2025 SC Bullit) chain grinding in big cogs

[ctcampbell]

Is this normal? The chain stretch on the top three big cogs seems quite intense so maybe it is, but it really doesn't sound good.

 

[Weeksy]

Take a photo of your casette/mech when in the last couple of gears so we can see the position and angles of the mech.

It depends what chainline the bike runs as to how far it goes over etc... but this is the problem with 12 speed that it's quite a big range of gears to ask for.

 

[irie]

Have you, or has someone else, recently replaced the chain?

 

[John_likes_bikes]

If your chain length is correct and lubed try 1-2 steps of micro adjust inboard/to the low gears. Overall shifting shouldn't change much but it may help the grinding.

 

[cantaloupe]

If you've absolutely hoofed your derailleur into a rock it might benefit from setting it up again.

 

[ctcampbell]

Have you, or has someone else, recently replaced the chain?

Replaced no, but in the grand scheme of things it a relatively new bike, bought late last summer.

 

[ctcampbell]

If you've absolutely hoofed your derailleur into a rock it might benefit from setting it up again.

I haven’t that I’ve noticed but that’s a good call.

 

[irie]

If you've absolutely hoofed your derailleur into a rock it might benefit from setting it up again.

Or even if you've fallen off your bike and the bike has landed onto the right (cassette/derailleur) side.