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SRAM GXZP Chainset + non-SRAM BB wobbles

Hello all

I've got a SRAM Force 1x chainset on one of my bikes and I can't seem to get it fitted nice and tightly unless I use a SRAM GXP BB. I've got a Hope BB sitting on the shelf and have just fitted an Ultegra, but no matter how tight I crank it I get wobble. 

The problem seems to be that the SRAM BB has a 'splined washer' on the NDS which holds that end of the spindle in place - no other BB has this and because the spindle tapers on the NDS it creates wobble.

If that even makes sense, does anyone have a solution for non-SRAM BBs?

Cheers

M

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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4 comments

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aegisdesign | 6 years ago
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The SRAM Splined washer btw is a bearing shield. It's not needed with the Hope BB AFAIK.

It's not there to hold anything in place. GXP BB axles push through from the drive side and just float there. The drive side bearing isn't clamped by anything. There's no preload like Shimano. They're 24mm that end. Usually there's a wavey washer that holds the bearing shield in place that side with SRAM BBs. If there isn't, stick an o-ring in there so the shield presses up against the bottom bracket. Otherwise the shield moves toward the crank arm and water gets in the bearing in no time at all. The bearing shouldn't be right up against the crankarm.

On the non-drive side, you've a bearing shield and the axle steps down from 24mm to 22mm at the spline. At the step, it pushes on the inside edge of the NDS bearing. You then clamp the NDS crank arm into the spline which clamps either side of the NDS bearing. Again, no bearing shield needed for the Hope BB as it has it's own sealed bearings.

If there's any lateral play, it usually means you've not clamped the NDS bearing enough. Use a torque wrench if you have one. If it wobbles up and down with the Hope BB, you've not fitted the GXP adapter. If it wobbles at the drive side, it's either a f*cked bearing or as I had once, the crank arm had become unbonded from the axle. Hmm.

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philhubbard | 6 years ago
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Shimano are 24mm axle and GXP axles are 24/22mm, hope this helps

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Welsh boy | 6 years ago
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You need an adaptor for the left hand side of the bottom bracket, Have a look at chain reaction for one of these ‘Hope Bottom Bracket Truvativ GXP Converter’ 

 

Here's the link

http://www.chainreactioncycles.com/hope-bottom-bracket-truvativ-gxp-conv...|ssxSICy0M_dc|pcrid|225604074714|pkw|%2Bhope%20%2Bbottom%20%2Bbracket%20%2Bgxp%20%2Bconverter|pmt|b|prd|

 

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workhard replied to Welsh boy | 6 years ago
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Welsh boy wrote:

You need an adaptor for the left hand side of the bottom bracket, Have a look at chain reaction for one of these ‘Hope Bottom Bracket Truvativ GXP Converter’ 

 

Here's the link

http://www.chainreactioncycles.com/hope-bottom-bracket-truvativ-gxp-conv...|ssxSICy0M_dc|pcrid|225604074714|pkw|%2Bhope%20%2Bbottom%20%2Bbracket%20%2Bgxp%20%2Bconverter|pmt|b|prd|

 

This

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