SRAM GXP FITTING IN A BB90 BOTTOM BRACKET

limoneboy

Now thismay have been covered , but i a trying tomfit my sram red chainset on a Madone 9.2 as i have moved to etap , all working with dura Ace chainset . problem is i have bought a bb90 converter kit for gxp and fitted it , it still seems to be adding pressure to the bearings and the crankset feels tight , normally this would e because its the wrong type of bb but this is the correct one , has anybody else had this issue or found a solution , if not i will have to stick to dura ace

cheers and in hope

The Rookie

GXP is designed to clamp across the non driveside bearing and have no preload across the two bearings, with adaptors both sides you may not be achieving that in which case as you do up the bolt you'll be over preloading the bearings.

By assembling the adaptor to the cranks you should be able to see how its working. Its also possible the total width is too big and pulling the driveside crank into the bearing (on a GXP you normally see 1-2mm clearance) in which case it will never work properly.

Possibly best to stick to using a Shimano crank where you can set a meaningful preload.

proto

Did you buy the Trek GXP kit?

My daughter's Madone 9 ran a GXP Quarq last year (and will again this year when the new one turns up). From memory the bearing kit consisted of two replacement bearings, a couple of dust shields and a wavy washer. Went together without issue.

Have you got the wavy washer and spacer on the drive side?

One of these?

limoneboy

Hi thanks both for your advice , the bearing kit is the same apart from the drive side bearing has plastic sleeve the same as the standard 24mm shimano maybe this is causing the issue , also the shaft does not seem to show as much on the trek bb . As far as I can tell though it's a trek bb. Where did you order yours ?