loose cassette

god1406

I know they are supposed to move side to side, but the chain's started skipping a bit under load recently, and under inspection the top two gears on the cassette move laterally and can be turned about 1/10th of a turn by hand.

I was under the impression the top two gears were seperate from the rest of the block, and should be tight against the other gears?

The whole drivetrain is just over a year old, but I do a lot of pedaling off the seat in high gears, could it be worn already?

MountainPete

They should definitely be tight. There should be a spacer behind the cassette to keep the top 2 gears tight - has it come off somehow?

nicklouse

what cassette? what hub? have you taken it to bits to have a look?

god1406

I have nearly every size removal tool other than this one apparently

Hub: Shimano FH M475

Cassette: shimano CS HG70


EDIT: I just turned the lock-nut and unscrewed it by hand with no effort. What the hell!

nicklouse

so it needed tightening. it happens.

god1406

i've tightenend it, but second-to-top gear is still loose and comparing it to top gear, the female splines look worn.

Although it might be that the male splines on the hub are worn. It is 5 years old i suppose.

Can the splined bit of the hub be replaced seperatley, or do I need a whole new hub?

nicklouse

yes it can but i would be checking the condition of everything....

the splined bit is the free body.

god1406

thanks for being patient with my rubbish terminology

I'll order a freehub sometime, and a new cassette, and probably a chain too...

as for the condition of the hub, the races are a little pitted, but since it's not my main bike and the wheel spins freely without being notchy, i'm not too fussed. Swapping the hub is something I'll only do if I really have to.

cheers.