So I just tried to put a Sugino crank (the single speed RD48) onto a Shimano 127 mm spindle BB, and the crank seems to hang way out on the end of the spindle! The bolts that came with the BB would barely hold the crank on. With the Sugino 103 mm square BB, the crankset is supposed to give a 42 mm chain line, and since I needed 54 mm, I figured the 127 mm Shimano BB would do the job. Nope! It's giving me a 60 mm chain line!!!
I'm very skeptical that bolting it on tightly is going to reduce the chain line by 6 mm. But I'm ignorant. I'm building a bike here for the first time, and this chain line business is by far the most PIA feature.
So now I'm looking at getting a White Ind. Crank set, which gives a 47.5 chain line with a 113 mm spindle BB. Since I already have a 127 mm, that should give me a 54.5 mm chain line, which would be awesome.
I did read that the Sugino BB was "designed" to go with the Sugino RD-48 crank set.
So my question is: will I really get a 54.5 mm chain line with the White Ind. crank? Or do I just need to tighten the crap out of the bolt on the Sugino? Does doing so really push the crank that far down the spindle? It's *very* snug at the 60 mm chain line point - can I get it to 54 mm? Or is this a case of parts that weren't designed to go together?
Everything involved is JIS - will tightening to the proper torque really move the chain line 6 mm further in? According to everything I've read, this should work - but I don't want to mess anything up in case I have to return it.
For others that run into these problems, I think I've figured it out. This crank set is the RD-2, that's what's stamped on the back. And it has a 45 mm chain line with a 103 mm BB, NOT a 42 mm chain line, as posted nearly everywhere online.
This is the source of my misery. I should have grabbed a 122 mm BB.