Shimano Indexing Adjustment

[inkeba]

I have a new road bike with Dura-ace drivetrain. The indexing is not quite right and it doesn't matter what I do, it will not completely shift correctly. My high and low limits are set correctly and everything seems properly aligned. Shifting down the cog to the highest gears seem to work fine. However, shifting up is not orderly. It misses a shft with a click. In other words, clicking the shifter once to shift up from gear 12 (highest gear) to 13 nothing happens, clicking again (click 2) the chain moves to 13; clicking again (click 3), nothing happens, click again (click 4) the chain moves from 13 to 14. All other gears upward work fine from there. I've tried adjusting the barrel adjuster many times (with 1/8 and 1/4 inch turns) with mixed results. If I adjust the barrel adjuster to make the shifting upward seemless, shifting down the cog becomes a problem.
I've also looked at the cables to make sure there are no frays or kinks and there are none.
Do you have any idea what could be going on and how I can possible fix this? Is the STI shifter for the rear derailluer defective?

[DaveM]

I would check the cable again. Even very slight kinks can affect this.<br />
Also look at the derailleur alignment, if this has gotten bent at all, you'll never get it adjusted right.<br />
Have you disconnected the cable recently? If the cable is not clamped in the derailleur in the right place, it can mess this up.
Did the problem come up suddenly or has it been getting progressively worse?

[inkeba]

It has always been like this but has actually gotten better...but not completely fixed.

[DaveM]

Is it new enough that the shop will still check it out for you? Unless something's damaged, DuraAce should shift very precisely, so something's not right. It sounds like you've tried the simple stuff, so it may be something more subtle that will be hard to diagnose without seeing the bike. I still suspect either something with the cable routing or how the cable secures on the derailleur. But hard to know. Sorry I don't have any other suggestions for you.