Originally Posted by
urbanknight
Not knowing the exact equipment, here are some thoughts:
1) If the chainring is mounted on the inside of the spider, can it be moved to the outside?
2) Can you respace the axle and redish the wheel to bring the ideal chainline a little closer?
3) What is causing you to need this chain so far out?
good questions; let me clarify.
1) the chainring is already on the outside (and currently with a chainline at 45mm); it's a Sugino single, and i like it and intend to keep it.
2) no; Rohloff internals are off-limits to me and other commoners; only access for Rohloff experts, and maybe wrist-watch repair people. Three internal planetary gears, many little little internal parts; things that when generally left untouched (save for oil renewal) never go bad. ain't broke? don't fix.
3) it's for a Rohloff hub drivetrain. but apparently, many a MTB triple outside-most chainring also runs at 54mm (not necessarily that the corresponding BB must meet that length), according to Rohloff, Sheldon, Thorn, et al.
I guess it's not a big deal then, to have a 123mm BB. I'm just so used to my 1x9 and its relatively close-in chainline that it seemed big. i might just get a 120 and use up 2-3mm of PW BB cup flex. as it stands now, my BB cups are asym. by ~1mm anyway, and it rides fine. Anyway, glad to have had my sleepy-head math 2x checked. Thanks all!