Originally Posted by
seedsbelize
I've ready to move away from cup and cone bbs and make the leap into the cartridge type, at least on this particular bike.
How do I decide what length to get? The spindle that's on it is too long, almost certainly, at 119mm. Something I grabbed out of the parts bin. The crank set is Shimano FC 1050, double, and the bike is a '79 Trek 930.
TIA
One thing to keep in mind is that most of these modern cartridge BB's are not offset. Unlike most classic cup-and-cone BB's, the modern ones are is usually the same on both sides - meaning you can get a good idea of where the spindle will land by dividing the length by two and comparing that with a caliper against the BB and existing taper.
-Kurt