I have 9 SPEED with
Ultegra with front and rear deraileur.
53/39 crank
12-27 cassette.

I seem to have developed some rubbing of the chain against the front derrailer
when I am in the 39-15 39-14 and such but not 39-17 and lower.

Where do I start to I adjust this to avoid the rubbing? I owuld not care if it was 39-13, 39-12 as that is a tougher adjustment and usually not there often.

thanks Rob