Spindle length help needed!
 

I am putting a new Sugino XD500 triple crank and new cartridge-type BB on a '83 Miyata 610. The old "cup and cone" BB spindle I removed seems long----124 mm (excluding the threaded ends). I think it was original, but can't be sure. The bike was a CL find, and I rode it very little before stripping it down.

Question: What length BB spindle seems right in this case? What will give me the optimal chain line? I am putting a new 7-speed Shimano freewheel on the original hub. The rear DO spacing is 126 mm.

THANKS!

107mm or 110mm should be the correct length for an older touring bike like miyata 6xx series.

some measurements would help narrow it down.
with your 124mm axle BB and crank arm installed, how far does the crank protrude from the chainstay? what is the chainline it gives you?

Well, I would need to re-assemble it to get that measurement---not sure. I do recall that a portion of the spindle was exposed in the old set-up. When I got the bike, it was road-worthy, but suffered from occassional "chain-suck" between the first and second rings on the original SR triple crank----which is one of the reasons I'm getting a new crank. Maybe the suck was caused in part by a poor chain-line??? The old BB simply needed to be repalced, so here I am...