nickw

Trying to install a PW BB on a new steel frame, a brand new Ritchey. I don’t typically chase threads in new bike frames but ran into an interesting issue and figured I would get some opinions here.

I have the (2) PW bb tools. BB was freshly serviced and hasn’t been used since, spins smooth on bench. But when I put it in the frame and tighten down to get appropriate chain-line / spindle offset the spindle is a tiny bit rough. Not bad or disturbing, but not PW smooth. I’m sure in practice it won’t be a problem and have noticed that it’s not uncommon for sealed bearings to spin a smidge rougher in place. With that said though, the only thing in my mind that would cause this is if the threads are not square and are slightly tweaking the BB shell.

Any thoughts? I’m at a loss.

dsbrantjr

Has the BB shell been faced so that the sides are parallel? This is a different operation from chasing the threads. You could try making precise measurements of the BB shell width at several places to get an idea.

Andrew R Stewart 

Well the common (if any Phil product can be described as common) Phil BB doesn't even contact the BB shell faces. So facing the shell will have no effect.


First thing I would ask is who serviced it and what was done. It is fairly common to get a bit of bearing compression when tightening up a BB unit. We have pulled really worn out/rough ones and then have the in shell to feel far nicer out of the shell.


One scenario I can think of is that the bearing cartridges are not completely/properly positioned on the spindle and within the outer barrel/sleeve. With pressure from the installation rings the bearings shift slightly WRT the inner and outer races.


I look forward to learning what's really happening. Andy

Slash5

It's possible the threading isn't concentric side to side. When press fit first came out, it was supposed to be one of the benefits that the BB shell could be machined with one setup.
I've got a Raleigh where I can't fully tighten the non-drive side cartridge bearing sleeve without binding up the bearings.

davidad

I hate to say this, but after using two Phils and replacing the bearings over the years I gave up and used shimano tapered BBs. They last much longer.