
MY CHAINLINE PROBLEM: My only issue is when in 39x23 or 39x25, I'm getting cassette rub/noise when applying serious race-pace torque on steep gradiant climbs (it's silent when climbing normally, even out of saddle - so I think a minor adjustment should rectify the problem). On the stand, I can see the chainline isn't great in these upper gears and the noise is coming from the chain links rubbing on (releasing from) the cassette teeth as the chain leaves the cassette. I'm sure this is the cause, it's not the chain hitting the spokes or anything else and the noise is present even when I overset the rear derailleur towards the spokes. Conversely, the chainline is pretty good in my 12 tooth sprocket and could handle the chainrings moving towards the frame a bit. I suspect my SRM crankset spacing moves the cranks out a mm or so compared to a standard crankset, thus my problem.
POSSIBLE SOLUTIONS?: I may be able to add a very thin spacer behind the cassette to move it outwards a bit, but I'm traveling at the moment and the only spacers I have don't leave enough thread for the lockring. When I get back home, I'll put a 9000 (non-SRM) crankset on the bike and see if it solves the problem. If so, or even if not, I wonder if there's slightly narrower bb cup (compared to the 9000 cup I'm running), which will move the cranks over a hair and correct the problem. I can't think of any other way to correct the chainline and still use my beloved SRM.
Hope this makes sense. Thanks much for any input!!
EDIT: See my below post re: the issue smooth1978 raised. So much for my being sure about the cause...
