Hi. I have just replaced the CS-HG50-9 11-32 cassette with a (used) XT M760 9-32. Both are 9 speed and I expected it to 'just work' without much fiddling.
I didn't adjust anything so need to set-up the rear mech properly but shifting is all over the place at the moment. Before invest time doing the set-up properly there's no reason why it wouldn't be compatible is there? I was under the impression that Shimano cassettes, mechs and shifters were pretty much interchangeable as long as they're for the right number of gears?
Either the chain is worn, or the old cassette is more worn than the chain.
There's no need to adjust your mech if you've just changed the cassette, you need to change the cassette/chain together.
So the used XT cassette is useless if it's at all worn and I don't have the chain which wore it? (It was supposed to be "one ride round the woods" old)
Existing cassette/chain is only about 50 miles old so I thought the chain would be fine. Is it likely to have already worn enough to cause this kind of problem?
If all if that is true they should mesh fine.
Is it the shifting or is the chain jumping over the cogs?
Yep, what Al said, if things are genuinely new it should work fine, something's amiss.
.. it's just feeling lazy, despite lots of messing with the shifter's cable tensioner.
I really need to adjust the rear mech to get the top/bottom limits set but I thought it should still shift fine in the middle. I was really only looking to make sure I wasn't wasting my time so will get on with it this evening. I spent many hours with a similar problem on my previous bike (after a change of cranks) which drove me mad and I never got working even with new chain & cassette - ended up buying a new bike. Trying to avoid the same frustrations.
Thanks.
N.
it's just feeling lazy, despite lots of messing with the shifter's cable tensioner.
try new cables/outers
could be all manner of things, but if you need to change the top and bottom limits, that suggests the cassette sits in a slightly different place to the old one, so all the gears will be out slightly. is it feeling 'lazy' in just one direction, or up and down the cassette?
Khani - thanks, but shifting was A1 before changing the cassette so I reckon all's well there.
cp - agree, had to remove the plastic thing which helps mimimise damage if it comes off the big cog so definitely sitting closer to the hub. Feels more lazy shifting down to smaller cogs but wasn't paying too much attention.
Appreciate all the advice but maybe it's a bit premature, I should just do the job properly & come back if I'm still having problems..
Check you haven't put it on wrong, missed out a spacer, not fully tightened it etc. There should be an identical gap between all the cogs and no wobble at all.
Where did you get the 9-32 cassette? Never seen a 9.
I really need to adjust the rear mech to get the top/bottom limits set but I thought it should still shift fine in the middle. I was really only looking to make sure I wasn't wasting my time so will get on with it this evening. I spent many hours with a similar problem on my previous bike (after a change of cranks) which drove me mad and I never got working even with new chain & cassette - ended up buying a new bike. Trying to avoid the same frustrations.
Assuming the old chain/cassette worked if you're needing to adjust the mech then the problem is not the transmission.
There may be time when it's worth admitting defeat and taking it to a bike shop, buying a new bike because the gears are a bit out is a bit radical!
cp - agree, had to remove the plastic thing which helps mimimise damage if it comes off the big cog so definitely sitting closer to the hub.
Doesn't that normally sit on the spokes and not touch the cassette? Shouldn't make any difference.
Where did you get the 9-32 cassette? Never seen a 9.
It's a typo, the only cassette to come in a 9 is Capreo, designed for folding bikes and what not, requires a special, smaller, freehub.
njee20 - LBS was always an option but it was 1993 bike and it was getting very hard to find parts, this was the last straw. And apologies for the the type, a 9 would be pretty a small cog!
cynic-al - yes, it does, but when I fitted the XT cassette it was rubbing and not turning freely so I removed it.
The XT cassette is on an alloy carrier which IIRC sticks out a bit past the biggest cog, so it could well have been fouling the spoke protector.
I'd have a fiddle with gearing first, shifting should work even with a 'worn' cassette, it's more the chain slipping and skipping teeth whilst in gear I find with a bad worn chain/cassette combo.
Just spin the freewheel by hand without the chain on it - make sure the smallest cog isn't wobbling - it's easy to put it on the wrong spline sometimes when fitting and not notice as it doesn't sit very far onto the freehub.
WAAAAAAY back, 8s xt cassettes had a thin steel/plastic spacer to fit behind the carrier - is it the csme with 9s?
Yes it is the csme.
if its going up the block like a rocket but lazy coming down there is too much tension on the cable. this would suggest that the cassette is sitting in a slightly different place on the freehub body. back off the cable tension, set both upper and lower limit screws and retension the cable. 5 min job. when you are tensioning the cable, only turn the adjuster in very fine increments.
all that assumes that your assumption of the xt cassette being 'like new' is true.
Thanks everyone - really appreciate the advice - will set it up properly tonight and cross my fingers..
Update - just in case someone looks in here in the future..
I adjusted the limits on the mech properly, spent some time getting the cable tension correct and re-lubed, now all's fine.
No hub spacer was required, cassette is definitely nearer to wheel centre than original but very slight & doesn't cause a problem.
For the weight conscious - the XT cassette is 100g lighter...
Thanks all for your input.