Originally Posted by
ThermionicScott
Just eyeballing it, I'd first make sure the chain isn't too long. Secondly, I'd move the axle forward in the dropouts -- indexing seems to work best when the axle is at the mid-point or further ahead. Lastly, I'd try letting out the B-screw a bit -- having the RD cocked backward too much increases the chain gap, which slows the shift. (That last thought might just be an artifact of seeing the bike in the small ring and a few cogs away from the smallest.)
Thanks for the suggestions.
First, I calculated the chain length according to Sheldon Brown's method of putting the chain around the large-large, and overlapping by one complete link. Not that I would use the big-big combo, so I could conceivably remove one more link, though Mr. Brown does warn against this. He writes:
If the chain is too short, it will be at risk for jamming and possibly ruining the rear derailer if you accidentally shift into the large-large combination. Never run with a chain that is too short, except in an emergency.
Second, would that even shorten the wheelbase even more and would cause more rub than having the axle further back? Sounds counter-intuitive, but I'm willing to give it a try when I get home.
Last, I will try to play with the B-screw and see if makes a difference.
Having test-ridden it, though only on a couple of gears, for about 10 km I gotta say I am really digging the ride. I hadn't ridden it for a long time. Even with a 23/25 combo f/b, it's smooth and comfortable.