Mountain Biking - Can I use a BMX bottom bracket?

In my search for a quality 68x113mm square taper bottom bracket for my MTB, I came across the Sinz Expert. It's listed as a BMX product, but the width and axle size fit the bill. I can't find any other size specs and am unfamiliar with BMX components. Anyone know if there's a compatibility issue here?

It has the JIS taper and English thread cups, so I see no reason why you can't. For some odd reason, it's listed as weighing about 100g less than a Shimano UN54. Strange . . . .

Yeah, I noticed that too. Not much more $ either, and no cheesy plastic threads. Seems like a no-brainer if it fits.

While I doubt that there is any compatibility issue I would be concerned about the strength of the bottom bracket you referred to. In BMX racing "Expert" refers to a frame size for racing bikes, it goes Mini/Junior/Expert/Pro/Pro XL. Expert is a frame size that fits kids in the 8 - 12 year old range, depending on how tall they are. Most "Expert" level bikes have a weight limit of around 110 - 125 lbs, this is usually based on the wheels (20 * 1 3/8) but the other components such as bars, cranks and bottom brackets are also built with a smaller rider in mind.

Thanks for the explanation andymac! Glad I didn't drop $ on a BMX BB designed for 125lbs. I'm about 160 and it's going on a singlespeed, so I probably would've snapped or bent the spindle before too long. Appreciate you kicking the knowledge...

in short: yes, if all the specs match(make sure:eek:), go for it - nothing should hold u back (except sometimes money:().


cheers, shawn