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I am trying to get a SRAM Apex crankset to work with a Shimano BBR60 Ultegra BB. I can either get it too tight or with a bit of play in the bearings.
It's going into a Cotic Roadrat with a 68 mm shell. I have got a SRAM to Shimano BB adapter of eBay but am having a number of problems.
1) The top hat washer on the drive of the cranks will not fit the Shimano BB. It has an outer diameter of ~26 mm while the Shimano BB ID is 24 mm so I've left it off.
2) The adapter is supposed to fit in the left cup from the back of the cup. But if I do that there is only 11 mm of splines sticking out and the LH crank won't bolt on.
3) I have tried putting the adapter in from the outside. I can then get crank on fine but if I fit the flower washer seal the bearings bind as soon as any torque is put on the crank bolt. If I leave the flower washer off then I have play in the bearings.
Everything is torqued up correctly.
Any suggestions? Or is it simply that a BBR60 BB doesn't work with SRAM?
Many thanks
You're just making things unnecessarily difficult for yourself. Either fit a gxp bb or a shimano chainset.
In an ideal world I would ditch the SRAM stuff altogether and stick with Shimano. But I've already got the bits so trying to save some money rather than buy a new set of cranks.
The BB adapter seller suggested filing off the step off the adapter so it fits in properly. The ultegra BB is extra small so doesn't have space for it.
Otherwise I'll fit a 105 crank and sell all the SRAM stuff.
Why don’t you just put in a replacement gxp bb - they aren’t expensive?
They are expensive given how quickly they wear out! I have all the parts already so trying to get it working before I spend any cash.
I can’t say I whiz through gxp bb’s but maybe I’m light on them overall. I think the last one did 18 months on an mtb before it got gritty.
leave the wavy washer and top hat off
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Sounds like your adapter is catching the inside of the cup and not seating home. I had that with one once
reduce the diameter a little with rough sandpaper
I've never found any of the GXP adaptors that great.
In the past I machined a spacer to press on the GXP axle so it was all 24mm, then used some RaceFace 1mm shims to take up any play / preload the bearings.
The adapter you've bought is to use a SRAM gxp chainset in a Shimano BB?
If so, I can't understand why the adapter OD is 26mm as the Shimano BB bearing ID is 24mm. The adapter is for the non drive side to sleeve down Shimano 24mm to the SRAM 22mm NDS axle diameter.
If your adapter is 26mm OD, it's the wrong one. If you use a SRAM GXP crank in a Shimano BB without an adapter, it will always be wobbly due to the 22mm/24mm NDS diameter differences.
Either correct adapter or correct BB. Your choice.
+1 on maybe the wrong adaptor.
I've used adaptors for a few years to avoid GXP cheese BB's, saved a small fortune by going to mid range Shimano instead. I've had one that was too tight, but the other two were fine.
matt_outandabout
Subscriber
I’ve had one that was too tight, but the other two were fine
Sounds like my ex girlfriends....