Hi all

I've noticed recently that my chain has been working itself loose during races. The pinch bolt is always tight, and the problem seems to be getting worse and worse - the chain actually jumped off during an endurance race on the weekend.

Is this a common problem? What could be causing it? I really want to get this fixed, as it's not very confidence inspiring!

Any help will be greatly appreciated

Edit - should probably mention that the bike is an NC30.

Sounds unusual and unlikely to be a fault of the chain adjustment system. What make/model of chain (and sprockets) are you running? I'm assuming you've spent wisely and bought a quality chain?

Not sure what brand they are, but they are reasonably new and in good condition. The bike doesn't actually live with me, so I'll check out the brand this weekend.

Is your hub assembled properly / worn out?

If the chain / sprockets are not at fault your hub could be slipping

You didn't grease the assembly while apart did you? A lot of energy going through those parts in a race. Anti seize is ok but not grease.
I've read a thread somewhere where a guy was having the same problem on the road due to this.

Neosophist wrote:Is your hub assembled properly / worn out?

If the chain / sprockets are not at fault your hub could be slipping

Pretty sure it's assembled properly, so I'm beginning to think it could be worn out. If I pull it apart would the wear be obvious? What sort of damage etc should I be looking for?

Mananon wrote:You didn't grease the assembly while apart did you? A lot of energy going through those parts in a race. Anti seize is ok but not grease.
I've read a thread somewhere where a guy was having the same problem on the road due to this.

I've never actually disassembled it before, but seeing as it's only started slipping recently I don't think it would have been greased.

I used to have this problem on my first nc30. Never did solve it as it was a roadbike, I just lived with the problem.

Get the hub out and have a look.

Shouldn't be too hard to see major wear on the outside of it.