Will a friction shifter solve my autoshifting issue?
I built a 1x9 out of a new frame and older specialized stumpjumper components. Derailer is an older XTR but seems to be in very good shape; shifter is an XT rapid fire; cable and housing is brand new.
I noticed the bike skipping and autoshifting about a week after putting it together. I fiddled with the cable adjustment en-route and that helped a bit. Later, I readjusted the derailer and put some grease on the BB cable guide, and all seemed well. I replaced the chain (old one grenaded) and shifting seemed to improve even more.
Fastforward to a few weeks later, and again I experience the dreaded autoshifting. I readjusted the derailer again and it seemed fine, but on the way to campus I get the annoying brief shift up and back down.
Am I not vigilant enough with my cable/der. adjustment? I'm considering abandoning the rapid-fire for a bar-mounted friction shifter if that would help, or would I just be throwing parts at the problem?