mtb with bmx bb shell

stickman

Saw a frame for sale, thought it would be ok to build up into a singlespeed but for the bb shell, as it would have been double or triple chainring would bmx cranks be any good for it? Would a converter to fit a regular bb be any good? Do they have to be compressed in with something like a headset press? I suppose they'd take a 73mm bb which I haven't got, although i've got two spare 68mm bbs!
Unfortunately it all seems like too much bother and money.

ride_whenever

HUH????

Can you post in a more coherent fashion?

mz__jo

A lot of mtbs are 68mm bb shell width. Usually 68mm sealed bbs can be fitted into 73mm shells, there is enough thread length. Bmx shells seem to be a bit of a jungle, encompassing everything including one piece cranks so you don't want to get involved with that unless you know what you've got (which I can't tell from your original post). I do not see why an mtb frame fitted originally with a triple chainset would pose a problem with the bb for conversion into a single-speed, people do it all the time. Of course if it is a downhill or trials frame life could get complicated but not impossible.

warpcow

You used to be able to get BMX BB adapters. They just xrewed into the frame and then pretty much any 'normal' BB could be fitted. They had them on CRC before, but I can't find them now.

I wouldn't say it would be a huge problem as long as you had all the details and knew what you were looking for.

stickman

Thank you both. Yes, the more I've thought about it the less I want to buy it. I saw some converters on CRC and they were press in ones.

nicklouse

fit what every you want. with the correct adaptors(s) anything will work Or just fit a BMX type BB.

PS asking in the MTB section would have been a better idea

stickman

Thanks

Or in the BMX section - if there was one to ask in