UKC

Some of you may know I have a new bike, I 'was' loving it

The groupset was all SRAM Apex apart from the front mech, which was microshift. As I had money left over on my C2W voucher I got a SRAM front mech. I replaced the other one and attempted to index my gears...

I have done this many times before with no issues albeit on shimano mechs

The front mech is ok

The rear will not engage the first four gears(largest rings)

The high and low limit stops are correct, and the 'B' position seems correct. The cables are less than 2 weeks old but when in the 6th cog I shift down the gears and it moves up one or two then just goes straight back to the 6th gear cog, I have tried adjusting the barrel adjusters on the cable but having no joy

Any ideas what it could be or is it a trip to the shop?

In reply to cfer:

Have you tried indexing from scratch? put it in 53/11 for arguments sake, then release the cable from the rear, pull it back tight, then play with the barrel by the mech to get it perfect?

The limit screws just adjust stop the chain falling off the cassette.

Give GCN rear mech a google for a youtube video.

In reply to IMA:

Agreed, click rear shifter to last click (smallest sprocket) release cable from rear mech, pull just tight and start from there.

In reply to cfer:

What they said, with the addition of making sure that when you've released the cable, the shifter is completely released to the end stop.

Possible it was installed partly shifted and is out of step with the cassette.

In reply to cfer:

All sorted, thanks guys