1966 Dawes Double Blue, 1976 Raleigh Gran Sport, 1975 Raleigh Sprite 27, 1980 Univega Viva Sport, 1971 Gitane Tour de France, 1984 Lotus Classique, 1976 Motobecane Grand Record
Cup and cone spindle length to cartridge bb
There must be previous threads about this, but I can't find them. I'm converting a cup and cone bottom bracket from a double to a triple. It's Sugino bb, for a 68 mm shell. The existing spindle is a 30-52-30, overall length 112. To convert to a triple, I would ideally use a 30-52-35 spindle, as I know from taking direct measurements with the crankset I'm going to use.
That's an overall length of 117. But if I go with a cartridge bb instead, a 118 would be too short, yes? Because all cartridge BBs are symmetrical? Am I correct in assuming that in order to get the length I need on the drive side, I would need the equivalent of a 35-52-35, or a cartridge BB with an overall length of 122? That means I have 5 mm more than I need on the drive side, but that's life, right? Or am I misunderstanding how all this works?
I'd prefer to stick with the cup and cone bottom bracket if I can find one the right length. But I may go the cartridge route instead. I recently bought NOS 32-52-35 spindle on ebay, but the guy is taking his sweet time about sending it--I wouldn't be surprised to find myself out both the 13 bucks and the spindle.
Shimano BB'a re not symetrical; the drive side is longer. Use Sheldon's exhaustive Database: http://sheldonbrown.com/bbsize.html#chainline
You can find specific reccommendations for specific Crank models and manufacturers. I had to adjust a chainline and found this url to be the only thing too aid me in figuring out the correct spindle length. Good Luck!