Cassette is stuck on hub

[greenstop]

Today I was changing out the cassette on my fairly new mountain bike, no problem with the existing cassette, just changing the gearing. I removed the retainer screw, but I could only remove the first three rings, the rest of the cassette was stuck on. Here is a picture, please tell me what you think. Thanks, Dan

[nfmisso]

Hi Dan;

Is it out of warranty?

toasted freehub body - must be aluminum.

Sorry, you are going to need a new freehub body; something like this: http://www.amazon.com/Shimano-FH-M760-Freehub-Body-Speed/dp/B000F5EGM8/

Get a steel freehub body, the weight reduction of aluminum is definitely not worth it, as your picture show.

Replacing a freehub body is not difficult; here are some instructions:
http://bikemagic.com/gear/how-to/mountain-bike-maintenance/freehub-replacement.html
http://www.parktool.com/blog/repair-help/freehub-service

As far as removing the remainder of the cassette, I would stick the old freehub body in a vice, and tap on the cassette with a hammer and chisel punch to rotate the cogs until they are out of groves that are cut into the aluminum. Do this on the insides of the cogs so as not to damage the teeth.

[Joe_W]

Yeah, you can see in the pic how the cassette has dug into the splines of the freehub body. There is a company (forgot which one... Zipp maybe or DT?) who actually has a very light freehub but with steel insets in the splines so that this does not happen. The costs are... astronomical and the weight savings are negligible, but it makes for a good story
And if it is fairly new: go to the shop and let them deal with it. This should be covered by the warranty. Failing that, maybe contacting the bike company directly could also work.

[greenstop]

Thanks for the help Nigel, that is very helpful. I thought maybe you would say I shouldn't pedal so hard, hah. I will check the warranty, Dan

[nfmisso]

(02-18-2014, 11:10 AM)greenstop Wrote:  Thanks for the help Nigel, that is very helpful. I thought maybe you would say I shouldn't pedal so hard, hah. I will check the warranty, Dan

Hi Dan;

Not likely I have only steel freehub bodies on my bikes, so that I don't run into what happened with yours. The steel ones are less expensive, and more durable. I set up my drivetrains so that the chain is the weakest link - and not be using weak chains . Chains are easy to replace and easy to monitor for wear/stretch.

[GeorgeET]

Have not seen that before. Yes you need a new steel hub as to getting the sprockets off you need to use a hammer and a drift or a sacrificial large screwdriver and than hit the sprocket a few times to get it back into the notch so you can remove it. Hopefully that is not the case with all the sprockets.