Yesterday, ride nearly had to end prematurely, as a result of a chain flying off the rear cog. Thereafter the gears never quite tried. Any tips on how to reindex on the trail? On this bike it's Sram Rival 1.
Chain flying off sounds more like a limit screw. If it is indexing then it can be done on the fly. Just turn the barrel adjuster while gently pedalling. You'll hear the change. When it goes quiet its good. To get it good go forwards and back a few times to find the middle of the quiet patch. Don't do this while bombing downhill
Thanks this is what I eventually did but unfortunately the barrel adjuster is next to the derailleur.
It flew off as I hit a root.
If the gears suddenly go way out of trim on a ride my prime suspect is a properly slipped cable or loose mech bolt rather than something that can be handled by the barrel adjuster.
Possible that the mech hanger has bent a little, throwing everything out.
I thought flies were single speed?
Bent much hanger tends to manifest as not indexing at one end or the other so you'll be fine in 1-5 but 9-11 won't index or vice versa.
You can get inline barrel adjusters for road bikes that you can either install mid cable or in place of the end caps. Makes doing it on the fly a doddle.
Thanks all. Not bent so have reindexed. Like the idea of mid cable adjusters as I have a I have on my mtb and road bike.
I've never found the inline adjusters much cop, either won't adjust or will go iut of adjustment all the time. You can get adjusters that sit on the down tube cable outer stop (if present) that work well, watch your fingers vs the wheel though!