Changing GXP Bottom Bracket

seanorawe

I have a Sram GXP 68mm shell bottom bracket, it was with the Sram Rival 22 group on my bike. I find the BB to be very clicky and noisy as soon as it starts to rain heavy, or I clean the bike. I even put had it re greased with really good quality grease, and it was better, but still nowhere as good as it should be.

So......

Without spending too much money, is it possible to swap out the BB for use with my Sram Rival cranks? or will I have to change the cranks too?

Are Hallowtech BB's made by shimano? is it simply a case of buying a 68mm hallowtech? I use a hallowtech BB tool to remove the BB to clean it.

Any other recommendations?

keef66

The GXP spindle steps down from 24mm on the drive side to 22mm on the non drive side. Shimano Hollowtech spindle is 24mm all the way.

http://weightweenies.starbike.com/forum ... 1&t=102485

So you can't just use a GXP chainset with a Hollowtech BB. Simplest solution is to replace the GXP BB with a new one of the same.

Or I'm sure somebody somewhere will be selling an adapter for the NDS that allows you to run a Shimano BB...

seanorawe

keef66 wrote:

The GXP spindle steps down from 24mm on the drive side to 22mm on the non drive side. Shimano Hollowtech spindle is 24mm all the way.

http://weightweenies.starbike.com/forum ... 1&t=102485

So you can't just use a GXP chainset with a Hollowtech BB. Simplest solution is to replace the GXP BB with a new one of the same.

Or I'm sure somebody somewhere will be selling an adapter for the NDS that allows you to run a Shimano BB...

From doing my own research, Hope have spacers to use GXP cranks on their BB's. However, I cant find any reviews on their effectiveness.

luv2ride

I run standard GXP BB on most of my bikes (including cx and winter bike) and have never had an issue with them. I'd say replace with the same as they're pretty cheap. Their "black box" ceramic BB comes up cheap now and again (although RRP looks expensive), but think I've read worse reviews for that than the standard version.

Moonbiker

gxp bb manual states dissemble & regrease after every ride in the rain.


https://www.sram.com/sites/default/file ... nual_0.pdf

Bearings require regular maintenance. Regrease bearings after 100 hours of use in dry conditions or immediately following any
significant exposure to water; such as riding in heavy rain or through water crossing

I have one on my cx and im on my 4th BB in less than 2 race seasons & thats with a few services.

luv2ride

Moonbiker wrote:

gxp bb manual states dissemble & regrease after every ride in the rain.


https://www.sram.com/sites/default/file ... nual_0.pdf

Bearings require regular maintenance. Regrease bearings after 100 hours of use in dry conditions or immediately following any
significant exposure to water; such as riding in heavy rain or through water crossing

I have one on my cx and im on my 4th BB in less than 2 race seasons & thats with a few services.

Looks like I'd better get greasing and servicing my GXP bb's. I've honestly never had to touch any of mine, but am now wondering whether they could/should run a little smoother? Certainly no noticeable drag and definitely no "graunching" or even clicking noises. That manual makes it look straightforward enough!