Is this drive train sound?

FreddieFixIt

I am having issues when racing where my chain won't stay on when it needs to - i.e fast rooty/rocky descending when another pedal stroke wouldn't go amiss.
Some people have suggested problems with SRAM and mixing and matching parts and was wondering if I should change some of the following 2x10 setup:

Shimano SLX Shifters Truvativ double crankset SRAM cassette Deore XT clutched rear derailleur SRAM X7 front derailleur SRAM PC31 chain

Thanks

nicklouse

They could be if all the right speed group.

But then again as you don't say they might not be.

Is the chain a typo?

FreddieFixIt

It's a 2x10, everything is 10 speed.
The chain is SRAM PC1031.

The Rookie

That should all work fine together.

Is the chain sized correctly?

Do you select the larger front ring when entering the fast rocky rooty descents which gives a bit better control of the chain tension? It also puts the front Mech closer to the ring so the chain can't move as far off the ring vertically before being constrained.

If it always comes off one side have you tried tweaking the front mech indexing to centre it better on the chainring - presuming it is coming off the front as you mention pedaling.

FreddieFixIt

It's a brand new bike so I was hoping the chain was the correct size and with my understanding of a clutched derailleur the chain shouldn't be bouncing about... I'm up into the big ring and middle of the back-block when descending, hit anything it pops off the big ring down into the smaller one (of a double) and grinds meaning I have to change down and then back up again.

The Rookie

FreddieFixIt wrote:

It's a brand new bike so I was hoping the chain was the correct size and with my understanding of a clutched derailleur the chain shouldn't be bouncing about... I'm up into the big ring and middle of the back-block when descending, hit anything it pops off the big ring down into the smaller one (of a double) and grinds meaning I have to change down and then back up again.

Show us a photo side on in big/big and it's easy to see if it's obviously wrong. I've seen a fair few new bikes with it too long.

Sounds like you may need to tweak the indexing of the front mech a bit as well.

FreddieFixIt

OK I took a few snaps of the chain in the big and big:
http://imgur.com/a/X7fyW

shindig

Add a blackspire stinger. I have one on my FS bikes. I have them on my clutch bike and non clutch bike. no drops.

Antm81

Judging from the heel rub on the cranks and the condition of the cable at the rear mech, you've done a lot of miles and it's in need of some maintenance. Unlikely to affect your chain retention but the outer is shot at the rear mech and no longer doing its job plus the inner has rusted, will certainly be affecting or start to affect shifting.

Front mech looks like it could do with some adjustment too

The Rookie

Chain looks too long, the mech should be pulled up nearly horizontal in big, big.

Front mech doesn't look centred over the ring and a stinger clearly won't help with this issue, so don't bother.