Does anyone know if there is a chainguide that can be used with three rings (XC crank)? A guide for two rings will also do. I do some UA-ish stunts and am always worried the chain will fall off, plus the noise the chain makes distracts me so much I can't concentrate on the technique properly (and it attracts too much attention from people around). Most guides I've seen only work with one ring. Many thanks in advance.