Originally Posted by Randyforriding .
... What's going on here and if the shifter starts refusing to catch again, do I just screw the barrel out more or what?
Yeah, that's pretty much it.
I switched from many years on Shimano brifters to SRAM Force and Rival a few seasons ago. It took a bit to get used to the subtle adjustment differences but overall I'm much happier with the wa SRAM shifts in the back.
In terms of adjustments I do the following:
- Make sure the derailleur hanger is aligned properly in both planes, this is a bigger recurring issue on the cross bike with the abuse that it takes but the road bike has been knocked a bit out of alignment at least once when it fell over while leaning against a wall and that really screws up the shifting.
- Check the limit screws before attaching the cable by turning the crank and applying pressure with your thumb to the parallelogram body
- Run the barrel adjuster all but half a turn in and snug the cable down tightly but not enough to move the parallelogram body and tighten the retaining bolt.
- Run through the cogs and usually I have to take a bit more tension out of the cable to get clean upshifts, I'll also pull steady but hard on the exposed cable run at least once and recheck that there's no excess slack in the smallest cog which often means another half turn to turn on the barrel adjuster.
- With SRAM I know I've got it dialed when either single or double up-cassette shifts (to a larger easier cog) followed by single down-cassette shifts (to a harder cog) work well. IOW, I'll walk up the cogs all the way to the largest cog in extra long throw movements that jumps two cogs at a time to make sure I can get up to the largest cog and each double upshift should be clean right onto the cog. It often takes an additional tweak on the barrel adjuster to get this right. Then I walk down three single shifts (each should be clean) and go back up a double and so on down to the smallest cog. That sequence makes it real clear if I have the right cable tension and when it's dialed the chain drops neatly down one cog per short push, two cogs up per extra long push and then it also works clean for the single long push up-cassette shifts.
That last step probably sounds a bit strange but with SRAM it seems the best way to totally dial in the action. I've had it seem decent for single up or down cassette shifts but end up between gears and rattling for the extra long double throw up-cassette shifts so testing that tends to flush out any remaining cable tension issues.
That's what I've found works for me and over time it seems to stay dialed in better than even my older DuraAce 7800 that seemed to need attention much too often though it worked great when it was dialed in perfectly.
YMMV,
-Dave
