Road Bike Not Shifting Into Big Ring
Fdr1 by ccsawyer on flickr fdr4 by ccsawyer on flickr.
Road bike not shifting into big ring. Where the shifter just isn t catching. Road cycling forum. It may be necessary to back it off to allow the chain to reach the big ring. If the chain won t run to the bottom of the cassette and shifts over the big cog into the spokes or vice versa it sounds like a bent rear hanger needs straightening or replacing.
The pawls get stuck with old grease. I walk through the steps to isolate and locate. Though it s unlikely to be this unless you ve mucked about with limit screws. In this case it s a road bike sti brifter but it also works for mountain bike trigger shifters as well.
Repeatedly shift on to the biggest chainring adjusting the high limit screw half a turn at a time until it does so without hesitation but does not overshoot the largest ring. The problem will be the shifters derailleurs or cables. If its a limit screw issue then if you pull the cable and pedal at the same it wouldn t move into the big chainring at all. I am often asked how to fix a bike that won t shift gears or will only shift to some gears.