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Sram Pressfit GXP Bottom Bracket disembled

dansclarkdansclark Posts: 7
edited May 2012 in MTB workshop & tech
When fitting a new Sram Pressfit GXP BB to my Zesty everything was going fine until i realised that the central tube on the drive side had not lined up correctly with the none drive side so they did not slot into each other completely.
So i decided to remove the non drive side only and have another go. When i punched the non drive side side out using the appropriate Park Tool BB tool set it pushed out the bearing and a slim metal/plastic washer (not the red coloured outer seal) and left the nylon cup still in place. As the bearing and this slim washer fell onto the floor i didn't get to see in what order they came out or which way round the washer should be. I removed the nylon cup and refitted that perfectly second time round. but i am left with the bearing and the slim washer.

I have repressed the bearing and the washer into the black nylon cup which is already in place on my bike and i'ts pretty much there but i have a nagging doubt that i may have the washer the wrong way round or actually it is meant to be the bearing first and then the washer i also notice that the centre of the bearing turns fine until the last half mm and then the centre part will no longer turn freely as if it's catching on the washer and i need to push the bearing out slightly until it turns freely again.

I've also refitted my XO crank to test and when retightening the non drive side bolt to the recommended torque settings the crank spins but not that freely (max 2 revolutions) so this is leading me to think that the bearing is not fully pressed into the cup but if i press it anymore it will probably catch on this washer and the central part will not turn?

Now here comes my question...

Does anyone know which way round this slim black plastci / metal washer should go?

It is not shown in their instructions or sram's technical manual so i've deduced it should definity be put into the nylon cup before the bearing, but maybe i'm wrong?

your help or guidance would be greatly appreciated ... ps i've already thrown the old BB away so i can't check that D'oh!

Posts

  • bennett_346bennett_346 Posts: 5,029
    The wonders of pressfit.

    Sorry, that wasn't helpful at all.
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