3 ms·
The bearings in external bottom brackets are much less well protected, and so more vulnerable to water and dust and so on. That means they need to be regreased
by twic 2y ago
The bearings in external bottom brackets are much less well protected, and so more vulnerable to water and dust and so on. That means they need to be regreased or replaced more often. I see people talking about doing that monthly, annually, whatever. I have been riding the same square taper bottom bracket since 2012, and it's doing fine.
The square taper per se may not be as good as a bolted spline or something. It is annoying to need a crank puller, but for me, it's been something i need once every five years or so, so not much of a problem in practice. So, compared to external bearing bottom brackets, a small disadvantage that buys you a big advantage. I have no opinion about the splined internal bottom brackets!
- sudosysgen 2y agoI've been riding the same external BB since 2015. The only people I've ever heard of replacing their external BBs are hardcore mountain bikers or people with exotic weird BBs. It's nothing special, just a run of the mill Shimano BB-52. While the bearings are a bit more exposed, they're significantly larger which means they can be sealed better. In practice they are pretty well protected fully sealed bearings. There's not really that much of a reason they'd have to be less protected than internal bearings.