Setting up a SRAM NX rear mech – gggrhhh

Setting up mechs has always been the job I detest most. Complete PITA.

Always been Shimano in the past, but now it’s a new NX mech doing my head in. Have fettled screws in all kinds of positions and set cable tension to hand-tight through to molgrip-tight.

Can’t get any logic rhythm. Nor can I find a guide specific to this damn mech. SRAM tech doc not doing it for me.

Can anyone point me in the right direction? This is the last job to do on this build. Ta all.

Ok, so I’ve set them up following the MBR guide.

Indexing fine, until I stop spinning for literally 5 seconds, then nothing. No clicking in the lever and no indexing. I then have to release the tension, click down to the high cog and re-tension.

Really annoying me now.

Any logic?

Try a new inner cable. My NX inner was bent inside the shifter so wouldn’t shift properly.

New inner sorted it straight away.

Great shifting performance now.

Sure, that’s an option. But the indexing was spot on. Then I left it and suddenly no more shifting. Same thing happened several times.

While I can see the latter being caused by a stretched/abused inner, I can’t see why the indexing would be perfect inbetween. Odd.

Right, I’ve stuck a new cable in and shifting is choppy. Did you find the top jockey wheel needs to be 1-2mm or 5-6mm clear of the big sprocket? I’m getting mixed results. Ta

B screw to close when in big cog?
Put it in big and dial it close enough to not cause clatter then back it off another mm or 3 for luck. And then back if off a mm or 2 more if that doesn’t work.

Well it’s sitting around 5mm clear at the mo and all gears are shifting v nicely. Took it for a spin and it’s bang on.

Weirdly I had to accept the L screw encouraging the chain into the wheel off the big cog when calibrating with no tension, in order for the chain to actually sit nicely on the big cog when re-tensioned. Otherwise the chain wouldn’t even get close to sitting on it.

Anyway, need to bleed the rear brake in the morning and then hopefully back on the trails after 2 solid years on the dark side steed.

Cheers for your help chaps.

Did you find this document (under the Service section)? B-screw should be set for 6mm gap (8mm on their other rear derailleurs)..