# New GXP bottom bracket too tight?



## speeddemon

I installed a new Team GXP bottom bracket on my road bike today and can't get the crankset to go all the way in on the drive side. There's about 3mm of space left between the crank arm and the cup. This is after I have used a rubber mallet and (gently) hammered on the crank arm. With the old bb, the crank slides on and off with almost no force. Are new GXP bottom brackets usually this tight? 

I'm not using any spacers. Tried with both my old Force crankset and a new Red crankset, same problem. 

I put a safety pin there for illustrative purposes:


----------



## cxwrench

is there an old bearing shield from your old bb still on the crank spindle? small chance it would happen to both you tried, but...

you riding in the rain a lot?


----------



## bikerjulio

deleted


----------



## nshadow

If you notice in the non-drive side bottom bracket cup, the bearing has a sleeve inserted into it that the crank spindle catches when you tighten the bolt. This can leave varying amounts of space between the drive side crank and the bb depending on how many spacers you're using. As long as there is no play in the crank you're fine. This design is to eliminate any type of sideways force on the bearings from tightening the crank.


----------



## SSRider

The cups of the newer rounded bb are actually thinner than the older squared off bb.


----------



## speeddemon

I found this thread that discusses the same issue. It's actually the non-drive side that is the problem. Verified this by removing the NDS cup, then the spindle on the DS would go all the way in. (Still had to use the mallet, though). When hand-tightening the NDS, the cup stops here:










That's about a 2mm gap, which can be fixed by one of the spacers that came with the BB. But should it really be like this? I haven't seen any mention of this in the manual.


----------



## cxwrench

have you measured your bb shell? normally you don't use any spacers w/ a road crank and a gxp bottom bracket. your frame may be slightly less than 68mm...


----------



## Seagoon

Are you sure this isn't a mtb BB because they are wider/thicker than road ones hence the tightness.


----------



## bikerjulio

the problem is consistent with SRAM using the same cup blank for English and Italian BB's in the new version of the GXP.

If this is the case, then the English BB's being 2mm narrower than Italian would need a 2mm spacer on the NDS cup.

I don't see anything in their literature to support this, but it's strange that so many are noticing it. We need someone to measure the cup width on both types.


----------



## speeddemon

My shell is 68mm. I measured the width on the drive side of the old and the new cups. The new cup was about 1mm narrower. 

Old:









New: 









I tried with a spacer on the NDS, but that messed up my chainline. The spacer is now on the DS and shifting works fine without having to adjust the front derailleur.


----------



## CleavesF

I have 3 bikes with GXP. Never had a problem, and none have any washers, AND no washers were ever supplied with any of the cranksets 

The GXP BB should be flush with your frame. If it doesn't go in, you need facing/reaming of your BB shell.


----------



## NEO Dan

Swapping from old to new Team GXP and I see the same gap:









It may actually allow for one spacer on the drive side cup, but this gap makes me wonder about my chainline really. 

The design of the new Team GXP BB is interesting in that the drive side cup outer bearing shield has a bushing integrated into it. This is why the final 1-2cm of installation is tight; the spindle diameter ramps up to a tight fit on the bearing shield thus creating a seal of sorts. Sure looks like a crud catcher, but the bearing shield rotates with the crank so there will be no wear or binding unless something is wedged in the gap that compresses the bearing shield and or scrapes against the bearing cup.

I'm contemplating pulling the crank and wiping the grease out of that area so it won't collect junk, and I'm also thinking a fat o-ring might be nice in that area if I don't put the shim in...


----------



## NEO Dan

It fits, this is the spot with the tightest clearance:









Obviously this is a big YMMV and I will be keeping a close eye on it just in case. 


I've not put my new cables on yet and so the FD limit screws have not been touched. 
This is what I see:









So it appears the new Team non-drive side cup may have a slightly more inboard spacing???


----------



## NEO Dan

OP needs to clean off all that extra spooge methinks. 

Clean stuff doesn't collect dirt and grime. :thumbsup:


----------



## cosmo333

GXP really isn't as complicated as it seems. Just different.

Drive side on the GXP system DOES NOT BOTTOM OUT. There should be a gap-the exact size varies with your frame but about 2mm. The NDS bearing has a smaller ID and stops the crank spindle as it goes into the NDS cup. This sets the chainline.

Non Drive Side does bottom out and tight! The system does not "preload" the bearings so making it too tight is really tough with normal tools. 6ft cheater bar doesn't count.

To install GXP in a road bike with a 68mm shell simply:
-install both cups, no spacers anywhere
-install crank and spindle
-grease splines
-install NDS arm and tighten bolt. Be sure it's fully bottomed and then you can check the torque (35ft lbs but it takes more than this to bottom the crank)
-ride, check bolt at end of ride
-if tight then you good until you take the crank off. If not tight then you need to tighten it.
-correctly installed you'll get about 1 1/2 turns when you spin the cranks.

Installed hundreds, never had a problem with this method.


----------



## 2128

thanks cosmo333!!! Let me try to reinstall mine tonight


----------

