I’m running 1 x 10 with the following:

– 34t ring mounted in the middle of SLX cranks
– 11 – 34t cassette
– SG XT Mech

The chainline appears spot on i.e. ring lines up with the middle of the cassette. However, when in the lowest gear (34-34) the cage of the mech is being pulled too far over by the chain. The consequence of this is that if you back pedal, the chain derails and drops a couple of sprockets.

The mech is aligned properly and the hanger isn’t bent. I’ve played with the B-tension to no avail. Is the chain too short? It’s not overtly stretched in 34-34 and is, what I consider, a satisfactory tension in 34-11.

Any ideas?

Cheers,

Paul