New chain old cassette?

on-yer-bike

Just changed the cassette from a new Record 12-27 to a Record 11-25 which doesnt have shark fin teeth although it must be 4 years old. The chain on the bike is new and the gears slip badly under, badly. Is this normal?

keef66

You've just discovered that a cassette can be quite badly worn without it being obvious on visual inspection. A new cassette will solve your problem.

If you're waiting for a cassette to exhibit sharks fin teeth before replacing it, you're trashing the rest of your drivetrain unneccessarily.

t4tomo

on-yer-bike wrote:

Just changed the cassette from a new Record 12-27 to a Record 11-25 which doesnt have shark fin teeth although it must be 4 years old. The chain on the bike is new and the gears slip badly under, badly. Is this normal?

Its normal if the 4 year old cassette is worn and should have been binned rather than refitted to another bike

on-yer-bike

The 4 year old cassette was working fine, although noisy, with an older chain that had just reached the .75 wear limit. This is the first time Ive experienced a worn cassette and I'm surprised at just how unridable it is. It hasn't been the only cassette Ive used for 4 years but I guess it could have done 10,000 miles max.

keef66

It generally comes as a surprise the first time you encounter it, because the cassette looks fine. Only by carefully comparing it with a new one can you see that the pitch of the teeth is increased by wear.

You could go on using your 4 year old cassette with the 0.75% worn chain and they'll mesh without skipping, but then you'd be wearing the chainrings too so it's generally false economy.

It is still a painful experience having to bin an expensive cassette.

on-yer-bike

Ill see if my wife wants to make jewellery out of it. Ive ordered a new one – Chorus, not Record. thanks