I'm having problems with my rear mech on my mountain bike. I have set both limit screws and they seem to be in optimal position. Shifting up from the highest gear to the lowest is fine but shifting in the opposite direction is a problem. The mech doesnt shift far enough across on the first index to move from the 1st cog to the 2nd. The shifter has to be indexed twice to make this gear change which means that the gears jump at the higher end on the 7th and 8th cogs. DOes anyone have any ideas as to what the problem might be?
I was just messing about with mine similierish sort of issues, fix one end and the other is jumping about.
Then I noticed the derailleur was a bit close to the spokes and I reckon the rear hanger had bent in a little for some unknown reason, effecting the arc probably.
Bending it out a little seemed to solve my problem.
Stickey cables are a big favourite for this sort of stuff.
Adjust down to first then, without moving the cranks, up to top.
With the slack available pop out the cable outers from the frame lugs and lube with a spray. The one down by the mech is the most likely to be gritty.
Put it back together, pull on the inner to settle everything down again and set up your gear change.
Sorry if I am teaching ou to suck eggs!
Good luck.
Cable tension
