I just finished assembling my new ride last night, and I have a question about fine-tuning the rear adjusting.

My drive train is Centaur 10s 13-26 with a 26-40-50 front. The rear derailuer is a medium cage.

The problem seems to be that I can adjust the shifting to work great in the higher gears, or the lower ones, but not both. This was done with the bike on the workstand; I am taking it out for a ride later on today.

Does anyone have any handy hints for dialing-in the shifting?

Thanks,

Scott

I noticed, on a new Record build, something similar. The shifting was not perfect across the full range. But once on the road, I did not notice anything was wrong, it shifted fine across the entire range of gears.

I suggest that you ride it and let it break in. The gears do shift a little different when under a normal load then when on the work stand.

I had a similar problem initially and it turned out to be related to a jammed upper pulley. It simply didn't float properly. The other reason (far more common) is too much cable resistance under the BB guide. This is especially common if you have an all nylon/plastic one. Some thick and tacky axle bearing grease applied to the guide will solve this nicely.

The Campy instructions (http://www.campagnolo.com/pdf/REAR_DERAILLEUR.pdf)mention aligning the cage on the small cassette cog first, adjusting the cage travel limit screw and adjusting the cable and casing as necessary. Move the cage to the fourth smallest gear to micro adjust the alignment, then move the cage to the largest cog and adjust the other limit screw. Perform this procedure without the chain in the driveline. Nothing unusual, though the fourth cog alignment check is notable. I've experienced the same sort of alignment difficulties that you've mentioned, but the driveline worked fine after walking through Campy's instructions and riding it for a few miles (w/ wrenches in the pocket)...
As Divve mentioned, things like cable stretch, running the cables through the casing turns and settling the cables into the guides after a few miles seems to smooth it all out.