Removing stuck cassette

[phantasmagoriana]

I'm attempting to fit a new cassette to one of my bikes - but having got the lockring and two smallest sprockets off (it's 8 speed), the rest won't budge! When I changed the cassette on another bike a few months ago, the cluster just slid off pretty easily once I'd got to the same point, but this one doesn't appear to want to go anywhere.

Aside from soaking it in Plusgas (which I've tried), has anyone any ideas on how to get these sprockets off? There's no special tool to use as far as I'm aware, and I can't really pull too hard as it might bend the wheel - I don't know what to try!

 

[gbb]

Some freehubs are prone to scoring, so it may be the sprockets are slightly out of line with the grooves, try turning the next sprocket a little and see if you can slide one off at a time.

 

[andrew_s]

I'd guess that what's happened is that the edges of the sprocket splines have made notches in the edges of the freehub splines, and got wedged in them.
See "Non Shimano Hubs", about 80% of the way down this page

I'd suggest getting 2 chainwhips, putting the biggest of the sprockets you did get off back on, and using one chainwhip on it to hold the freehub still whilst you use the other to try and move the stuck sprockets back out of the notches. Work one sprocket at a time, rotating the stuck spocket as far back as you can, then trying to pull it off.

 

[RecordAceFromNew]

My guess, is those stuck sprockets have eaten into the (possibly alloy) freehub, making it look something like this:

If you just leverage/pulll those stuck sprockets out, they might do further damage to the splines of the freehub, but then the freehub is probably damaged anyway.

One possible solution is to use two chain whips (or one chain whip and one old chain plus a a vice), one on a loose sprocket, with the other on the next stuck one, applying torque on the stuck one in counterclockwise direction.

However if all the stuck ones are pinned in a cluster (e.g. with 3 tiny allen bolt), you should release the freehub from the wheel (usually with a 10mm hex key) and release the sprockets from each other before proceeding - otherwise the stuck ones may well win in the tug-of-war against the free one.

You might have to leverage/force the sprockets off if all else fail. Releasing the freehub from the wheel first will help avoid damaging the wheel.

 

[Red Light]

If it has made grooves in the freehub and you are replacing the cassette you might be better just to take off the old freehub complete with cassette and replace it with a new one and new cassette.

 

[phantasmagoriana]

Thanks for the suggestions. In the end, having had no joy at all (and not wanting to invest in another chainwhip) I'm afraid I wimped out and took it to the LBS.

Now off, freehub body cleaned and new cassette ready to go on. Strangely enough, the freehub is fine - no indentations of the type pictured above. I think it must have just got seized with years of grime and dirt (not all mine - it was second hand).