Cassette skipping...

[gungi]

my rear cassette sometimes skips a tooth or something every now and again, makes a big CLACK sound! wtf.

 

i have never taken one apart so don't know whats cracking inside there:) and do i need that special LBS tool to get in or what?

[Speed Devil]

Take the skipping rope away and it should behave itself

[AndreZA]

I doubt the cassette skips a tooth. It's more like the chain. There is also nothing inside a cassette to check. It might be the freewheel.

 

 

[Spinnekop]

Sounds like the cassette is loose.  Tighten it.

Special tool, yes.

 

Looks like this:

 

http://www.totalcycling.com/images/large/19303_170016.jpg

 

Spinnekop2008-10-22 03:31:34

[Red Zone]

You could have a tight link in the chain, roll the chain around and see if there is a link that doesnt hug  the cluster.

 

your cluster could also be worn. are the teeth work into shark fin shapes

[gungi]

it doesn't seem to be the chain and my cassette is in good nick... would it maybe be the freewheel thingy? i really have no idea cause i am relatively new to mtb's and have never stripped one before... oh and where is the best place to get all these special tools that bikes need?

[Wannabe]

Take it to your LBS to check out. Safest option for now.

[IanJ]

Does it happen if you freewheel for it bit and then start pedalling again?

 

I have had that problem before when the freewheel mechanism was worn.

 

[gungi]

that must be it do i need the special tools? i would also like to change bearings while i have it apart if possible?

[Wannabe]

Take it to your LBS to check out. Safest option for now.

[gungi]

okay okay, LBS.

 

i just hate someone else do something i am perfectly capable of... i am mechanically minded, can stip a mx bike down to a box of parts (and then re-assemble) just dont know bicycles yet... i will take it to the Mavericks later though and ask them

[Wannabe]

Good thinking. And while you are there, ask them if they'l mind if you watch the "Spannerman/person" in action, especialy if he/she is going to be stripping the freebody/freehub. Find out what tools would be needed (the one's that work on your bike)to do the job correctly, get a quote and purchase the CORRECT tools if you want to be able to do it yourself in future.

Believe me, you'll want the freebody/freehub to be 100%, it can lead to nasty things happening to you should it fail in the middle of a powerstroke. Wannabe2008-10-22 05:35:40

[Mudsimus]

Its probably the freewheel. JB posted something on this somewere else. Servicing the freehub will most probably solve the problem.

[Johan Bornman]

A short, sharp snap can have one of three origins.

 

1) Poor shifting

2) Freehub body (modern bikes don't have freewheels anymore)

3) Loose cassette.

 

Pick one of the above and remedy as suggested by others here.

A freehub body is not serviceable, even brave people don't go in there. They are relatively cheap and are simply replaced.

However, I won't replace it just because it snaps every now and then. If the snapping bothers you, go ahead, do it.

 

Don't take the unnecessary caution to heart, this is not a part that causes catastrophic failure. Even your goolies are safe.

 

To replace a freehub body, make sure you have the exact replacement. Quote the right hub part number (Shimano FH-540 or whatever) and take a good look at your existing one before fetching the new one. Even better, take the old one with you.

 

To remove it you need to remove the axle. Do this by using a 14mm cone spanner and a 17mm flat spanner and loosen the locknut and cone on the LEFT hand side of the wheel and pull the axle out from the right. You did take off the cassette? Right.

Now remove all the balls and put them in a clean anchovy bottle with some paraffin. Wipe the races with hundreds of tissues, rags and earbuds. Put a 10mm allen key into the axle hole on the freehub body side and unscrew the freehub body. It will require huge effort on the allen key. This is normal. It unscrews anti-clockwise, so don't think you're doing something wrong when it doesn't budge.

 

Replace the body in the same way. Just before you go to the bike shop, check if those bearings that are by now clean, are serviceable. They should be smooth, shiny and sparkling. If not, buy new ones.

 

1/4 inch for the back, 9 per side. 3/16th for the front, 10 per side.

 

 

Squirt a ring of grease onto the races, glue the bearings in there, replace the axle gently from the right and adjust the cones.

 

Cones should be tightened so that there is just a small perceptable play when you wiggle the bearing/axle by hand. On the bike, the QR skewer compresses it and then you should feel no wiggle.

 

The wheel is perfect if there is no wiggle when clamped in the bike and, the wheel settles on its heaviest point each time you spin it a little. If it settles randomly, the cones are too tight.

 

Go ride.

 

[gungi]

wow... JB that was helpfull! Really appreciate the effort you just made to help a fellow mountainbiker! i will have a look tonight, and take the wheel to the LBS in the morrow if it gets too hectic:)

[Piernas Flacas]

 

 

Squirt a ring of grease onto the races' date=' glue the bearings in there, replace the axle gently from the right and adjust the cones.

 

 

[/quote']

 

I thought u didn't like it?