DanO220

I am frustrated that the current bottom brackets (with bearings inside the shell) are considered throw away components by the overwhelming majority of bike mechanics. Even though a $65 bottom bracket might be touted as having 'servicable and replaceable' bearings, try finding a shop that will actually rebuild one for you. In my case, at least, every last one of them have said 'just buy another one'. That's hard to swallow when a good BB is so expensive.

So much for the rant. My question is: are the new outboard bearing bottom bracket/cranks (ala Durace, FSA MegaExo) totally superior to the internal bearing ISIS designs? Enough to try and convince my wife I need to replace my fancy carbon cranks? Or should I just keep buying BB's once a year?

DanO

53-11_alltheway

FSA makes a intergrated internal BB design called Mega Tech that is supposed to have larger bearings with a better stiffness to weight ratio than Mega-Exo. (outboard bering designs like Mega Exo are 75 grams heavier than designs like this https://www.fullspeedahead.com/fly.as...axid=29&pid=75

Unfortunately, I don't think it works with conventional frames.

FSA makes some good BB in ISIS format. I'd try one of their better ones (Mega quad?)

You going through a BB in a year? Wow! (Is this for real?)

berny

Outboard bearings can be larger in diameter which makes for less friction = easier pedaling. They also distribute the pedal force load over a wider area (longer axle) which would help keep the axle straight, arguably reducing flex but it is really such a minor variance I doubt it's worth stressing about. Just buy a new good quality std. BB.