Bicycle Mechanics - Sachs Quartz and Sram Shifters, Help

I set my bike up with Sachs Quartz rear derailer, Sram 9.0 ESP 8spd shifters, Sram 5.0 8spd cassette and LX front derailer. My problem is that when I shift the rear derailer it tends to hop over gears one and a while 1-2 shift is usually fine but then it will hop from 2-4 or something to that effect, it seems to only effect the middle cogs on the cassette. The top to cogs and the bottom two cogs seem to shift fine between them, but other then that I keep skipping over the other cogs, and sometimes it will half engage another gear, like the indexing isn't working or something, I've tryed everything, what can I do? I just set up a 9spd Ultegra rear derailer on another bike today and it was a 5 min job, why is this giving me so much grief?

Sounds like you have a 2:1 rear der with a 1:1 shifter. This of course is incompatible, and will not work unless you do some real fanagaling.

Damn is that the problem? That sucks :( I thought that the Quartz was 1:1 as like the Sram XO and all the other derailers that are derived from the D.I.R.T design.

Try clamping the derailleur cable on the other side of the clamping bolt from it's original clamped position. Doing this will sometimes change the pull ratio enough to make the shifting work. It used to work when I had to make Suntour cassttes work with Shimano or Sachs' derailleurs.

Unless your der. is D.I.R.T compatible then you will have the little problem you are having. There were some Sachs der's that were made before SRAM bought them that were 2:1 ratio der's.

Thanks for the tips guys.