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Wierd Sram GXP Cups problem

craigentycraigenty Posts: 960
edited November 2010 in Workshop
I'm fitting a new chainset for amate of mine.
It's a SRAM Red chainset and he's bought a new GXP BB cup set specifiaclly for SRAM.

However when I fitted it (I know what I'm doing becuase I've fitted the same sytem to my bikes numerous times in the last 2 years) the drive side crank arm was clunking around. I took the cups out and the drive side bearing has an inside diameter of 25mm - SRAM drive side should be 24mm, at least it is on all my other SRAM bearings on the workbench and that's what the dimeter of the axle is.

Anyone know of a problem where the wrong bearing might have been put in at the factory or has my mate been sold a mountain bike BB set or something like that. It's definitely a GXP for SRAM.



  • rakerake Posts: 3,204
    youre right, it should be 24mm id. shimano have 25mm shimmed down to 24mm with the plastic dust shield journal. i dont know if mtb are different, if not you have the wrong bearing.
    got any pictures. does the other side have a journal pressed in to reduce it to 22mm. they should also be 8mm wide. if wider (i think 9mm) you probably have somehow got a shimano bb in the wrong box.

    Sram = 37x24x8
    Shimano =37x25x9
  • nicklousenicklouse Posts: 50,675 Lives Here
    sounds like a fault set.

    GXP is GXP whether it is road or MTB.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
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