Which Sram BB for FSA Crankset.

big_southern_jesse

I mullered (Yes, it's a technical term!) my cranks after rounding off a hex head bolt removing them when I needed to fit a new bottom bracket.

I'd bought a shiny new Shimano Saint BB80 BB to fit, but then needed new cranks.

I ended up buying FSA cranks because they were on a stupidly big discount (see here: http://www.chainreactioncycles.com/fsa- ... prod151693 ).

Which clearly don't fit the shimano bb. But I figured that discount was worth using a different bb, and they were described as including a threaded bb. GReat.

Except they came with a push fit. MEh, okay, so go and buy a new SRAM bb, it's not that expensive compared to the discount.

Have bought and fitted a SRAM GXP which I believed was their standard bb, but whilst the spindle slides through the drive side oh so nicely, it certainly won't fit through the non-drive side, which seems to have a smaller diameter.

I've been over the FSA and SRAM websites a few times, but can't find any charts for compatible parts.

So can anyone shed some light on what bb will fit the cranks above?

It's a 68mm internal thread on an On One Inbred.

Thanks folks,

Jess.

The Rookie

GXP is 24mm diameter drive side and 22mm none drive.

FSA mega ESO is 24mm at both ends the same as Shimano HT2, I believe you can use the Shimano BB but have never tried it, certainly the Hope BB is the same for FSA and HT2. You say they 'clearly' don't fit the Shimano BB, did you try?

http://www.fullspeedahead.com/tech/

big_southern_jesse

The Rookie wrote:

GXP is 24mm diameter drive side and 22mm none drive.

Okay, that's what it seemed, I was just surprised that there would be a stepped/tapered spindle...

The Rookie wrote:

FSA mega ESO is 24mm at both ends the same as Shimano HT2, I believe you can use the Shimano BB but have never tried it, certainly the Hope BB is the same for FSA and HT2. You say they 'clearly' don't fit the Shimano BB, did you try?

http://www.fullspeedahead.com/tech/

I did try. It seemed a "close but no cigar" moment. I could push the spindle about half an inch into the drive side before it went from a tight fit to wedged solid. Took some gentle tapping to get it off.

Should I have persisted and tried harder?

cooldad

Yep, whack harder.

The Rookie

My Shimano needs a slap with the palm of my hand hard enough to hurt 'a bit' to get it in, you will of course have put a smear of grease in both top hats to aid the insertion process, you should never goes shoving things in without making sure they are lubed properly you know.

cooldad

Pah! It's just like the Australian definition of foreplay. "Brace yourself Sheila."

big_southern_jesse

I did the slap it by hand, and stopped, fearing that I was about to wedge it solid.

It felt like one was designed metric and one imperial and they were close enough to nearly fit but not quite. I thought Shimano and FSA might use slightly different dims that weren't compatible.

It's definitely gonna need a rubber mallet to insert if I try.

Should it absolutely definitely fit?

The Rookie

It should absolutely definitely fit, the only FSA cranks that cause issues are the road carbon ones as they use a narrower overall fitment (would still insert just fine anyway).