Or am I unable to fit without a 8 mm gap showing on the drive side?
Bought some SRAM xx1 carbon fat bike cranks off here, got a gxp 100 mm bb for English thread.
Fitted by no issues tried pushing on cranks no way can I get it to sit flush. I can when not in the bb, so assembly is okay when not in frame.
I have added a spacer either side of bb.
What am I doing wrong here?
Have you measured the B&B shell to make sure it's 100mm? I can't imagine why it wouldn't be, but..
Have you measured the B&B shell to make sure it's 100mm? I can't imagine why it wouldn't be, but..
Yep, I have fitted the drive side bb with sleeves with arrow facing drive side and then pushed on the chain side crank fits flush.
Thread the other, off side cup, and it forces the crank out to 8mm ish gap.
?????
Sram do 2 versions of fat bike cranks for different set ups. Sounds like you've got the 5" version on a 4" frame.
The gap on the right side is a feature not a bug on gxp cranksets.
You did nothing wrong.
Am I right that the space between both cranks and the chainstays is the same?
They crank are
Sram XX1 Carbon Cranks, GXP, 170mm, Black Grey, 168 Q Factor, direct mount chainring compatible,
Frame rear wheel spacing is 177mm.
Are there two versions, if so how do I know what I have
Fatbike standards are a real joy...
Dear lord yes....
Flows yes same space
There are 2 versions of GXP bottom brackets and 2 versions of crank axles. The one you have is probably the one i have on my X5 cranks. The bearing dia on the drive side is 24mm, and the other side is 22mm. So the crank axle on the non-drive side stops on the inside of the 22mm bearing and you have ugly few milimeters of the axle showing on the drive side.
But thats apparently perfectly normal from what i read 🙂 So no worries.
Also, SRAM made gxp BB is rubbish, i switched to [url= http://accent-bikes.com/en/products/parts/bb-sets/bottom-brackets/bb-ex1/bb-ex2 ]ACCENT[/url]
and there is no single grain of sand inside since april 2017 of abusing my bike.
Any other thoughts folks?
What's your chainline? 168mm Q-Factor intended for use with a 100mm BB, expect it would be 55-58mm. You sometimes need to give the crank a firm tap to seat correctly in the driveside bearing - I wouldn't expect to see a gap on DS
100 mm bb on the frame
Firm tap offered on more than one occasion.
Any ideas where I can find the definitive information please.
There are two replies above telling you it's normal with those cranks.
It's normal with those cranks.
It's also *. Really procreating excrement.
After a few rides the plastic 'top hat' in the drive side bearing will work its way out of the bearing and into that gap leaving you with wobbly creaky cranks in the middle of nowhere.
After several rides of re-setting it each time you'll send a message to SRAM tech support and get no answer despite having just spent a lot of £££ on their product that presumably was never actually tested, they've just added x mm to their normal cranks (where x is for some reason too many).
You'll then buy an aftermarket BB without the plastic bit thinking that will work. It wont. The whole bearing will now drift out of the shell.
Then you'll buy a hope BB. It's a utter cluster of procreating excrement that you should have to spend another £70 on top of the cranks but there you go. The plastic shields on Hope BB's act a bit like circlips in retaining the bearing in the shell. If I have any more trouble with it I'll replace the drive side one with a proper circlip (the NDS one is needed as the GXP axel clamps the adapter, which clamps the plastic shield and the bearing).
Other options
1) add 3x more 2.5mm spacers to the BB shells, this kinda works, but the drive side bearing no longer sits on the machined bit of the axle, so it creaks.
2) 3D print a variety of spacers in small increments to see if you can pack out the space on the axle. Eventually this works, but still creaks, and by this point the bearings are utterly *ed and you swear you'll never buy another ****ing SRAM product ever again.
Right cheers
So another thread will be why did I choose SRAM over Shimano, but that is another day
So another thread will be why did I choose SRAM over Shimano, but that is another day
Shimano don't make a 100mm crank.
Rummage in your parts box until you find something which fits the gap. The inner race of the old bearing worked for me. Was fun hitting the old BB with a hammer until it exploded too 🙂