Rough Drivetrain in Highest Two Gears
I'm getting close to finishing up my current build---a secondhand Gunnar Roadie built with an Ultegra SL compact double groupset. I've adjusted my derailleurs to where the shifting seems spot-on, but I've noticed that the drivetrain runs pretty rough in the highest two gears, running more smoothly once I move up to the third smallest cog.
It seems like a chainline issue, with the chain traveling over the big ring and small cog at enough of an angle to create resistance and sound "chunky." I've measured the chainline, though, and it seems reasonable. The front measures at the normal 43.5mm. The middle of the cassette is within a millimeter or so of this.
Is this normal for a double chainring setup? Or is there something else I should be looking at?
Thank you.