Hardest Bottom Bracket Question Ever!

jamespalmer100
jamespalmer100 Posts: 24
edited April 2015 in Workshop
So, I have Cube Agree GTC Pro which I've built myself. As seen here - http://www.cube.eu/uk/bikes/road-race/a ... nred-2015/

It's fitted with a BB71 bottom bracket as seen here - http://www.chainreactioncycles.com/shim ... -prod61803

I was running an Ultegra crackset with no problem. The chainrings wore so I decided to treat myself to a nice new Sram Red GXP crank. Fitted a new BB71 bottom bracket and purchased some of these adaptors - http://www.chainreactioncycles.com/hope ... lsrc=aw.ds

There's a lot of play in the crack and it doesn't tighten properly.

So where have I tone wrong? Do I need this? - http://www.chainreactioncycles.com/sram ... -prod75586

Comments

  • thebadgerboy1982
    thebadgerboy1982 Posts: 266
    i think you have it spot on with the gxp bearings. i had a similar problem using a gxp in a bb30 set up. the preload was a bugger to set
    Thebadgerboy1982@gmail.com
  • Monty Dog
    Monty Dog Posts: 20,614
    GXP uses a different bearing design vs HT2 - with HT2 you need to side-load the bearing to take out axial play whereas GXP bearing width is more critical. You could try using some shims behind the BB cup to meet the GXP spec, or simply fit a GXP
    Make mine an Italian, with Campagnolo on the side..
  • crikey
    crikey Posts: 362
    I don't understand why cyclists choose to try to combine bits from one manufacturer with those from another.
    Sometimes it works, but far more often you get the kind of situation described.
    Why bodge something?
  • keezx
    keezx Posts: 1,322
    People have one part (frame) and want a certain part to fit it (crankset) what's wrong with that?
    Some people like to leave the path's determined by manufacturers.....
    A HT2 adapter can be used with GXP with an additional spacer (Hope) without any problem, because the left bearing has to be 22 mm internal.
    No preload is needed.
  • cswitch
    cswitch Posts: 261
    but OP fitted new BB. Common sense would suggest installing the correct BB rather than introducing additional likelihood of creaking interfaces. Anyhow my advice would be to knock it out and just put in the right GXP press fit BB. I have a nearly new one you can have for £12 posted. It was knocked out with the right tools, spins fine etc. removed after about 5 rides it as put on a power meter. PM me if you want it and I can email you some pics.
  • tonye_n
    tonye_n Posts: 832
    cswitch wrote:
    but OP fitted new BB. Common sense would suggest installing the correct BB rather than introducing additional likelihood of creaking interfaces. Anyhow my advice would be to knock it out and just put in the right GXP press fit BB. I have a nearly new one you can have for £12 posted. It was knocked out with the right tools, spins fine etc. removed after about 5 rides it as put on a power meter. PM me if you want it and I can email you some pics.

    ^^
    This... sounds logical.
  • Moonbiker
    Moonbiker Posts: 1,706
    My gxp BB lasted less than 100 miles doing cx, seem they don't like wet & mud, or will need regular dissaembly & re-greasing.


    http://velonews.competitor.com/2012/12/ ... eet_269323
  • keef66
    keef66 Posts: 13,123
    "Anyhow my advice would be to knock it out and just put in the right GXP press fit BB. I have a nearly new one you can have for £12 posted. It was knocked out with the right tools, spins fine etc. removed after about 5 rides it as put on a power meter. PM me if you want it and I can email you some pics."

    Shimano's advice is not to reuse their press-fit BBs once they've been installed / removed because they can be damaged in the process even if the correct tools are used. Not sure what SRAM say. Shimano are however notoriously risk averse, and you'll likely get away with reusing one if it hasn't been abused during removal. For £12 it's worth a flutter.

    If you can get the Shimano one out sympathetically I might be able to find a home for it in my CR1 :D

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