Gears skipping in just one gear

heavymental

My dad has bought himself a cheap fold up bike. Its got 6 speed Shimano grip shift gears which work fine apart from in the 2nd giggest sproket. It works fine in the other 5 gears but slips when under load in that one gear. I've fiddled with the barrel adjuster but can't get that one gear to work. It looks to be centred right on the sproket too. Any ideas? I know its cheap but it should work fine if the other gears all work ok shouldn't it?

John.T

It could be a damaged tooth or just a worn cog.

geoff_ss

Just about guaranteed that it's a worn sprocket. As a get out you can sometimes get away with reversing it to use the, unworn, back of the teeth, but that's not always possible with modern set ups. Did it all the time on screw-on, non-indexed, blocks. Otherwise the only answer is to live with it or replace either the sprocket or the whole cassette. If you do the latter it might also be worth replacing the chain at the same time.

Geoff

heavymental

Hmm...trouble is, its a new bike. Shouldn't be worn at all. Think maybe I'll try adjusting it from scratch to see if that gets rid of it.

rdaviesb

The sprocket is definitely damaged. I doubt, if it's a cheap folder, that it's a decent quality part. Even if it is, take it back.

John C.

If it is a new bike take it back and get a new block , chain etc. When you buy new , that is what you should do. That is what you pay for. If you try to fix it you may invalidate the warrenty.