What are my chances of getting a new loose bearing bottom bracket that will fit square taper cranks? The one in an old Malvern Star frame is rooted, hoping to convert her.
I’ll go for a crawl around the bike stores tomorrow, but thought there could be some advice had this evening.
Most LBS should be able to sort you out with a few loose bearings, if not i’m sure they will have caged bearings that will do the trick. Then again if the cups and axel have wear and pitting it’s probably worth replacing the whole lot as their not that expensive.
I don’t just need bearings, I need a whole new assembly.
It’s the one that has a big cup the width of the bottom bracket on the drive side that the non-drive side lockring screws into. The axle is bent and the lockring is threaded. The bottom bracket on the frame has no threads at all, nothing screws into the frame.
I heard a rumor that you can get threadless cartridge bottom brackets, made for threaded bottom brackets in worthwhile frames, although I’m a bit skeptical of the safety/reliability on a fixed bike.
I ran a YST BB for around 12months, no problems until one of the bearings failed - for whatever reason it had been fitted with one sealed and one shielded bearing and the shielded failed, not surprisingly.
Sitting in the parts box with a pair of replacement bearings, 113mm JIS taper, if it is any use to you.
That BB is a Malvern Star proprietary insert that clamps into a larger-than-normal unthreaded BB shell. You can replace the cups and axle in the Malvern Star insert with any English threaded BB cups and axle. You may be able to fit a Shimano cartridge BB into the Malvern Star insert but I’ve not tried it.