My friend has been asking me why his bike makes loud crunching sounds and the chain jumps. He's in Cornwall and I'm not, so I got him to send me a pic of the cassette.
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Initially he asked if it was the freehub, but after changing it he tells me he's just put a new chain on it. 🙄
Could this be the cause?
The new chain is skipping? Usually you can have a couple of chains on a cassette before it wears out. Maybe he has trashed both. I would be replacing both. Really hard to tell much from that pic.
It only looks worn on the top couple to me, maybe he should ride it gently and let it bed in to the chainwheels?
I'm sure I've done that before and had a mix-age drivetrain settle-in.
Sorry, yes, he told me after he changed the freehub that he had also just put a new chain on it.
Can't see anything from the photo and its really hard to tell anyway.
new chain + old cassette = recipe for skipping though. Old chain back on, or new cassette.