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Hope bottom bracket problem (GXP) - ongoing with photo!

frankspencer1979frankspencer1979 Posts: 525
edited January 2013 in MTB workshop & tech
Have removed my Hope BB from my previous frame, where it was working perfectly, give it a wipe over, re-greased the threads and popped it into a new frame and now it doesn't work!

When I tighten up the bolt on the non-drive side crank, it pulls it all together and the whole thing seizes up. I can push the cranks round, but they don't spin freely, there's a lot of resistance.

I have the GXP conversion in the non-drive side as The cranks are Truvativ. The frame has been faced and I've got the correct amount of spacers so I can't figure what's happened.

The bearing in the non-drive side spins smoothly, the drive side a little less so, I popped the seal off and cleaned up in there and re-greased, but that didn't help. It's only as I tighten the centre bolt when things get really stiff. I'm not doing anything differently to when it was on my old bike, and I don't think I've done anything which should balls it up!

Anyone any ideas!?
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Posts

  • supersonicsupersonic Posts: 82,708 Lives Here
    Mine are like this, just a standard GXP. The 1 bolt system locks and preloads the bearings, not the best way. Is it really hard to turn? They often free up a bit with use.
  • It's not hard, i don't have to strain! But it does take effort, it would be noticeable resistance whilst pedalling. On the hope how to video where he installs gxp cranks, he "locks off" the bolt and the cranks still spin freely. I jyst don't get why it worked fine on the old frame but now it's gone dodgy!?
  • bennett_346bennett_346 Posts: 5,029
    What is the shell width? Should be no spacers either side if it is 73mm, that would cause it to drag.
  • It's 73mm, i have no spacer non-drive and chain device in lieu of drive side spacer (i measured it, it's 2.5mm like a spacer.) I have been told this is the correct set-up, and the hope instruction sheets suggest this layout.
  • supersonicsupersonic Posts: 82,708 Lives Here
    I'll have to double check that, thought it was no spacers at all.
  • bennett_346bennett_346 Posts: 5,029
    Its definately no spacers at all. That's why you're having issues.

    Hope probably say driveside spacer because shimano cranks run a driveside spacer on 73mm shells.
  • You're right! I'm happy to be wrong! :D Didn't realise there'd be a difference coz it's GXP. Took the Stinger out and now it all spins nicely. Will have to see how I get on without a chain device now.
  • mrmonkfingermrmonkfinger Posts: 1,452
    It's 73mm, i have no spacer non-drive and chain device in lieu of drive side spacer (i measured it, it's 2.5mm like a spacer.) I have been told this is the correct set-up, and the hope instruction sheets suggest this layout.

    Despite posts to the contrary, you already had the correct spacer setup.

    My guess:

    1) the chain device plate is probably quite thick (thicker than a spacer) and its all now too wide for the GXP cranks.
    or
    2) maybe the BB needs facing, its a little over 73mm and too wide for the GXP cranks.

    Incidentally, I could never get a GXP crank, a hope BB, a 73mm BB shell and stinger, to all play nicely together. There was no clearance for the chainrings.

    I ended up getting an FSA crank in the end, which did work. By the time I'd sold on the chainrings, and the BB that came with the cranks, it only cost me about £20.
    supersonic wrote:
    The 1 bolt system locks and preloads the bearings, not the best way.

    There's no pre-load on GXP old chap - the cranks clamp around the non-drive bearing, and float in the drive side bearing.

    FSA, Shimano, RaceFace, all went the preload route.
  • bennett_346bennett_346 Posts: 5,029
    It's 73mm, i have no spacer non-drive and chain device in lieu of drive side spacer (i measured it, it's 2.5mm like a spacer.) I have been told this is the correct set-up, and the hope instruction sheets suggest this layout.

    Despite posts to the contrary, you already had the correct spacer setup.

    My guess:

    1) the chain device plate is probably quite thick (thicker than a spacer) and its all now too wide for the GXP cranks.
    or
    2) maybe the BB needs facing, its a little over 73mm and too wide for the GXP cranks.

    Incidentally, I could never get a GXP crank, a hope BB, a 73mm BB shell and stinger, to all play nicely together. There was no clearance for the chainrings.
    There are NO spacers on a 73mm GXP setup. I can guarantee you that. Hence you could never get it to work properly.
  • mrmonkfingermrmonkfinger Posts: 1,452
    There are NO spacers on a 73mm GXP setup. I can guarantee you that. Hence you could never get it to work properly.
    the OP wrote:
    Have removed my Hope BB from my previous frame


    A Hope BB with GXP converter requires one spacer (or chainguide or E type derailleur) for this setup.
  • bennett_346bennett_346 Posts: 5,029
    I don't see how, surely its the axle width that decides the amount of spacers, which is fixed regardless of BB?
  • bennett_346bennett_346 Posts: 5,029
    In that case the hope ones must be really narrow since the standard gxp bb doesnt use any. Either way chain devices don't seem to work on this setup so it's irrelevant.
  • Previous Vitus frame was 68mm shell. I had one spacer non-drive side and the Stinger on the other, that worked nicely.

    On the new frame (Piglet) it's a 73mm shell. I tried it with just the Stinger, and it all locked up pretty stiff. The Stinger looks thick, but measures at 2.5mm like a single spacer.

    I've removed the Stinger, have no spacers at all and now it all spins nicely. Bennett, you be correct :wink:

    Cranks are Truvativ X7.
  • nicklousenicklouse Posts: 50,675 Lives Here
    GXP is designed to not use any bearing preload. There should be a gap on the drive side.

    Raceface. GXP. and 73mm bb shells and a chain device are in most cases a NONO.

    Have fun.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Still a bit of a problem, I've got it all tightened up, but there's a slight gap on the non-drive side, see photo's. I gues this is gonna allow water seepage into the shell and cause problems!? It doesn't seem right. But a spacer is defo too big, I'm confused.

    IMAG0896.jpg
    Drive side

    IMAG0895.jpg
    Non-drive side

    Please ignore the mashed teeth, it's my first time! :oops:
  • bennett_346bennett_346 Posts: 5,029
    Are the threads chased?
  • I've not had them chased. But each cup can be screwed in all the way individually, it's only when they're both in that the above situation occurs (gap appears on the side which is screwed in second.)

    The shell is defo 73mm, measured and Ragley state it as 73mm in the spec sheets; and the BB is designed for both 68 and 73mm so it should fit!? I don't know what's going on. I'm looking forward to sticking the decals on, I should be able to cope with that!
  • sensi10sensi10 Posts: 68
    I think the problem is that your meant to install the none drive side cup first , then the drive side cup 2nd which should leave the gap on the drive side which is where there should be a gap of 2.5mm for a spacer / chain guide. I think that the frame needs facing and that is why the crank is locking up.
    Have you measured your frame with a vernier as if the frame has never been faced and there is paint on there it may be slightly over 73mm?
  • sensi10sensi10 Posts: 68
    Also this may be a illusion in the none drive side picture , but it looks like the cup is not sitting square in the frame the gap on the left looks larger than the gap on the right side ?
  • sensi10 wrote:
    I think the problem is that your meant to install the none drive side cup first , then the drive side cup 2nd which should leave the gap on the drive side which is where there should be a gap of 2.5mm for a spacer / chain guide. I think that the frame needs facing and that is why the crank is locking up.
    Have you measured your frame with a vernier as if the frame has never been faced and there is paint on there it may be slightly over 73mm?

    Christ, now I'm more confused than ever. On the Hope videos, the dude installs the drive side first so that's how i've done it now, although I've tried both ways. The gap i'm left with now is way smaller than a 2.5mm spacer/chain device. The frame has been faced.

    As it is now, no spacers/small gap, the cranks spin lovely. With a spacer, s'no good.
    sensi10 wrote:
    Also this may be a illusion in the none drive side picture , but it looks like the cup is not sitting square in the frame the gap on the left looks larger than the gap on the right side ?

    I'll check on this tomoz when I can see what I'm doing, but I think (hopefully) it'll be an optical illusion coz of the close-up with the camera.
  • sensi10sensi10 Posts: 68
    This is strange if the frame has been faced ? Maybe the other guys are right in saying that 73mm does not need spacers, as that is the case for the sram gxp bb 68mm requires spacers 73mm does not . The hope website does show a spacer on the drive side cup with a 73mm frame maybe when using a shimano crank.
    Also is there a chance that when facing to much has been removed and thats why your left with a gap ?
  • bennett_346bennett_346 Posts: 5,029
    Shimano cranks run a spacer with a 73mm shell. Sram do not.
  • nicklousenicklouse Posts: 50,675 Lives Here
    So you are not fitting the centre sleeve correctly. Remove it and fit the cups.

    Is it fine? Then look at what you have marked/damaged on the sleeve and/or the cups where the Sleve slides.

    And measure the shell.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse wrote:
    So you are not fitting the centre sleeve correctly. Remove it and fit the cups.

    Is it fine? Then look at what you have marked/damaged on the sleeve and/or the cups where the Sleve slides.

    And measure the shell.

    I'll check this tomoz. Sounds like I've broken it now :roll:
  • You should be running a 2.5mm spacer on the driveside. This is because the hope BB uses a different dimension of cup in comparison to the standard truvativ bracket placing the bearing in a different position.

    Try the whole lot built up with a Hope 2.5mm spacer instead of the chain guide and see if that works.
  • bennett_346bennett_346 Posts: 5,029
    Chain guides are 2.5mm so it shouldnt make a difference, unless the cranks or chainwheels are rubbing on the chain guide plate.
  • Chain guides are 2.5mm so it shouldnt make a difference, unless the cranks or chainwheels are rubbing on the chain guide plate.
    It should be 2.5mm but is it :?:
  • bennett_346bennett_346 Posts: 5,029
    Chain guides are 2.5mm so it shouldnt make a difference, unless the cranks or chainwheels are rubbing on the chain guide plate.
    It should be 2.5mm but is it :?:
    Yes. He has said he has measured it. And if they supplied them any thicker or thinner that would be a major recall since it wouldn't work on anyones setup.
  • nicklouse wrote:
    So you are not fitting the centre sleeve correctly. Remove it and fit the cups.

    Is it fine? Then look at what you have marked/damaged on the sleeve and/or the cups where the Sleve slides.

    And measure the shell.

    I'll check this tomoz. Sounds like I've broken it now :roll:

    Ok, I've taken the sleeve out and both cups screw right into the frame and sit flush as they should, put the sleeve back in and the gap appears!

    I've cleaned everything up and inspected closely and there's no obvious sign of damage. I can't really see how I can install the sleeve wrong, it just slides into place?

    The shell measures at 73mm measured with tape measure, I don't have access to callipers at the moment.
    Chain guides are 2.5mm so it shouldnt make a difference, unless the cranks or chainwheels are rubbing on the chain guide plate.
    It should be 2.5mm but is it :?:
    Yes. He has said he has measured it. And if they supplied them any thicker or thinner that would be a major recall since it wouldn't work on anyones setup.

    The chain guide measures at 2.5mm. I've also tried with a 2.5mm spacer and get the same result (I.e the cranks lock up with spacer in place.)

    It seems putting a 0.5mm spacer in would get rid of the problem, but not solve it I guess!
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