SEAtrain

Hi,
I have a sealed cartridge shimano bottom bracket that feels like it's grinding when mounted on the bike. If I remove the cartridge it spins normally. It starts to grind when I torque down the removable ring.

I followed the procedure found at the Park website:
https://www.parktool.com/repair/readhowto.asp?id=94

The less I tighten the better it feels; however, if I leave it loose enough to eliminate the grinding then it is not torqued properly.

For context, I am refurbishing an old, Speacialized Stumpjumper rigid frame (1992-ish). So I kind of expect to find worn parts.

What is going on here? Is my cartridge worn out?

Thanks!

HillRider

It's likely your bottom bracket shell faces aren't exactly parallel and when you tighten down the non-drive side cup, it warps the cartridge enough to bind slightly. Either have the bb shell faced or don't tighten down the nds cup too much. All that cup has to do is locate the cartridge so it needen't be torqued as much as the drive side.

SEAtrain

Interesting, this makes me think that the shop didn't install it correctly. I see no evidence that it was faced. I would expect to see some paint removed in the facing area.

Thanks for the response, BTW.

gt35built

Is the non drive side cup plastic?

Did they use the right length bb? Chances are this is not the problem

SEAtrain

Not plastic. I don't know for sure the correct length BB was used, but I've been riding it with for years and I suspect it has always been this way.