This guide is to show you how to complete a rear gear roadside repair with what’s left of your cable if it fails.
Your rear gear cable can fail for any reason and the mechanism will shift the chain to the smallest rear sprocket. This annoying problem won’t end your ride. It may make getting up hills difficult and be bad for your knees. You can resolve it temporarily by manually moving the chain onto your desired sprocket. This trail side solution will not cause any long term problems whatsoever. It is a solution intended for split outer cables and snapped inners usually.
Once the chain is in position you should remove your gear cable from the gear lever on the handle bars. chop most of the cable leaving just the barrel fixing end and a 100mm length of cable. Feed the inner cable into the hole in the rear mech’s barrel adjuster it usually feeds into. Tighten the cable using the pinch bolt as usual and adjust the chain line on the rear sprocket by screwing or unscrewing the barrel adjuster.
The same result can be achieved without using your gear cable. You will be limited to the smallest sprockets on a normally returning rear mech. The method involves the limiter screws being set all the way in. This will restrict the mechanisms movement to the third or fourth smallest sprocket.
This rear gear roadside repair will make it stay in position until you get home. You will not be able to shift gears until the job is resolved properly. Depending on the barrel adjuster, you may be able to change between two and three gears manually however. You can do this by rotating the barrel adjuster on the bar mounted gear lever or using the rear mechanism adjuster.