Chain slipping

apple eater

Having had my gears and derailleur looked at closely when riding it appears that the chain is slipping when under load in high gears (i.e when climbing rooty single trails and the like) it's fine in the low gears when building up downhill and flat speed.

Is this a sympton of a stretched or worn chain, if so aprt from the chan what else should i change to cure the problem?

Chunkers1980

Could be a few things. Try a new chain first, if that still does the same then you'll need a new block too

lpretro1

More likely worn chainrings

cooldad

Try adjusting the mech first. B screw and check indexing.

delcol

i would try to reindex the gears and check all the limmit screws etc before i go buying new bits..

if it is the chain that has stretched then it could require new cassette and and chain rings to as they may be worn,, (depending what sort of mileage they covered)

Chunkers1980

From OP "Having had my gears and derailleur looked at closely"

By who? Would suggest they are indexed correctly by someone who knows what they are doing?

apple eater

Checked under load while riding and then later that day taken to a bike shop near me. It's definitely Not trying to change gear.

MontyDog

Sounds like chain wear. The chain doesn't stretch as such, the inner pins wear out lengthening the distance between each link. If it's slipping now, then you will probably need a new cassette at the very least. When I replaced my chain after leaving it too long, I had to replace the middle ring on the front also. Buy one of these http://www.tredz.co.uk/.Ice-Toolz-Chain ... _37701.htm and check regualry. Replace chain just before it reaches the wear limit. It's much cheaper in the long run.
I.M.H.O.
Regards,
Kev.