I know that the crankset manufacturer recommends a bb size for their crankset. Does the required bb get longer if the dropout is wider? I would guess that 130 and 135 wouldn't make much difference but what happens when the dropout grows to 145 or even 160? Or, do I adjust the chainline by adding spacers to the drive side of rear wheel?
I'm thinking of getting a new tandem frameset with 145 spacing and my current tandem is 135 and I like the bicycle setup totally. I'd like to buy as few components as possible.
I know that the crankset manufacturer recommends a bb size for their crankset. Does the required bb get longer if the dropout is wider? I would guess that 130 and 135 wouldn't make much difference but what happens when the dropout grows to 145 or even 160? Or, do I adjust the chainline by adding spacers to the drive side of rear wheel?
Paul, with most 145 rear drop-out spaced tandems you can stay with the same BB spec'd for solo road triples. Burley and Co-Motion do and there aren't any chainline problems. Going to 160mm rear spacing requires a wider BB spindle. For example, Co-Motion with 145mm rear spacing uses the Shimano 118.5mm Ultegra T splined BB with the Ultegra tandem cranks. Santana with 160mm rear spacing uses a Shimano 129mm Ultegra T splined BB for the same tandem cranks. The 129mm BB's are made for Santana plus they also use a 73mm BB shell.
