could i use a Saint BB on a road bike with a Tiagra chainset

stardude

as the title says really

i am swapping over from internal to external BB due to some thread damage on the drive side. the external will go in further and use more threads.

i read this morning that the Saint BB has longer threads on the drive side cup as chain devices are usually installed, so a longer thread will end up with the same number of threads engaged when devices are used.

so could i use a saint BB with a new tiagra chainset on a road bike?

cheers

adam

nicklouse

you may need to have the threads in the BB re-cut.

stardude

nicklouse wrote:

you may need to have the threads in the BB re-cut.

to use the saint bb? or in general?

or do you mean to have them extended into the BB shell?


only the first 3-4 threads are damaged. so the shop is chasing them through

nicklouse

to allow you to use any MTB BB in a road frame.

Saint/Deore or any other. the only difference between Shimano Road and MTB BBs is the amount of Drive side thread.

kevolution

The OP has already said he's aware of this, which is why he wants one.
You may need to cut some new threads a bit deeper into the frame to accomodate a Saint BB, but with the longer thread engagement, the plastic spacer between the cups will not fit. You'll have to leave it out and grease the inside of the BB shell, o cut the specer down to fit.
Either way, the bearings will be exposed to corrosion more than they would usually be.

*AJ*

Why would the plastic spacer not fit?? ....

nicklouse

*AJ* wrote:

Why would the plastic spacer not fit?? ....

the space between the bearings is less.

Road BB do not use any spacers.