SRAM X7 cage length - nightmare adjusting

fanatic278

Hi,

I'm having problems setting up the chain length on my new Commencal Meta 5.5.3. If I set up the chain length to be long enough for large front chainring and large rear sprocket then there's way too much sag in the small/small cog combination.

There seem to be no happy comprimise on chain length, so I'm left with the conclusion that my SRAM X7 rear derallieur cage length is too short (it's the one that came with the bike - so I would have thought it should be correct). How can I tell if I've got the right cage length? I assume I should have the long one rather than the medium one, but not sure how I can tell the difference - it's not written on the mech.

Cheers
Chris

nicklouse

you should not be using Small and Small.

chain length. Around both big rings and add one link.

As can be found on Parktools

fanatic278

Small - small is unadvaisable agreed. However, the problem with chain slack persists all the way to the fifth cog at the back, i.e. the mech fold up on itself and the chain rubs along itself over the cage.

I've measured the chain length as advise by Parktools - big ring to big ring, bypassing rear mech then add two links (with max compression on suspension).

Turrican

Sram x7, i have sram gearing x7 all round firstly agreed when setting up the tesnion of chain first loop the chain round the largest cog on abck and largest on front now take the slack up by taking links out then there is a small adjuster very small screw where the mech goes in to the frame but on side adust the tension of the mech by rising the mech up or down closer to the cassette i dont meat the high low screws it should have one as my does and makes difference to chain tension too as i built my bike up from frame to running if can get a pic for you i will to show you, when i get time soo busy any way hope that helps.

nicklouse

if you go onto srams webby you can see the difference between the long and the medium.
I think the metta was specced with the medium which would mean that the chain could be set too long for the mech or too short for the gear set. Guess which is safer?

new bike get the shop to set it up to how you want it or adapt to work with it.

fanatic278

Capt Yeti - I think you might be talking about the B adjustment screw just behind the fixing point of the mech onto the frame. I had a fiddle and it made a small difference, but not enough.

My cage length is 8cm from centre of upper jockey wheel to lower jockey wheel. Medium cage? Why wouldn't Commencal put a long cage mech as standard?

nicklouse

Ask them.

something about riders not wanting a long cage.

Turrican

Yeah Frantic i was thanks, i have 0, Sram x7 in long and it brings the jockey wheels up closer or away from the cassette depends which way you turn the screw thats what mine does as mine is long and does make bit difference but not loads hope get it sorted