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Tight Chainset - Wh...
 

[Closed] Tight Chainset - What have i done wrong?

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[#11684055]

Just putting on a GXP BB and Chainset. As soon as the non drive side is vaguely tight (no play) the whole thing stiffens up and is difficult to rotate. What have i done wrong??


 
Posted : 15/01/2021 12:46 pm
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Does it have a preload adjusted that is not backed off?

If not, probably incorrect combination of BB spacers. For example, of your BB shell is 73mm you don't need any spacers.


 
Posted : 15/01/2021 12:54 pm
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Does GXP have a wavey washer, have you missed that?


 
Posted : 15/01/2021 12:55 pm
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Its a 68 mm shell with a 60/73 bb in it with two spacers provided so i am using both spacers. Argh!!


 
Posted : 15/01/2021 12:56 pm
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You have seen this then ?


 
Posted : 15/01/2021 1:02 pm
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New frame? Or are you replacing a BB that worked fine in there before?

I had a frame where the BB threads weren't cut in line. More obviously wrong that yours, but if they were slightly off, it might cause the problem you're having as you tighten it up?


 
Posted : 15/01/2021 1:02 pm
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Sounds right - 68mm should be one 2.5mm spacer either side.

Are the cups fully inserted (threaded or push-fit?) and the bearings fully home in the cups?

Which GXP crank is it? I vaguely remember there being some variations in axle length (although that may be road).


 
Posted : 15/01/2021 1:04 pm
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Ah ha fast haggis has it. Its a rival chainset. So road. Just binned off both spacers and voila! All sorted. Love this place sometimes.


 
Posted : 15/01/2021 1:12 pm
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Triffic.


 
Posted : 15/01/2021 1:13 pm
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Are you sure the frame is 68mm? GXP works by clamping the non-drive bearing between the axle's step, and the crank, the drive side just floats in it's bearing, so there shouldn't be any preload on the bearings to cause tightness(in fact there's normally a gap behind the chainset,the cause of may threads on here).


 
Posted : 15/01/2021 1:17 pm