They are tricky as tend to rub on trible chainsets , bu tfing slightly bending helps

sounds bad but sometimes a must to get rid of all rubbing, first loosen cable make sure mech cage goes right back to the frame, adjust barrel on gear lever central but more closed,pull cable tight and tighten up allen bold on mech,the screws stop the mech going to far both ways so not te derail chain, then adjust using barrel till all works well, it take fiddling i TBH i find tripples harder to set up than doubles and generally use doubles on both road and MTB's as dont use the outer ring much on a MTB, hope this helps ryan,
