# Sram Red BB30 install question



## bike867 (Feb 2, 2011)

I have the little retaining clips installed in the grooves in the bb shell. Then I've pressed in the outer bearings using the park adapters and the headset press tool (one side at a time). After doing so, the outside face of the bearing is roughly 50 mm from the outside edge of the bb shell. Included with the bb are two black aluminum spacers that are 50 mm wide and the little crib sheet included with those say that for 72 mm shell to not use them, but for a 68 mm shell (mine is 68 mm) to use them. The Sram website doesn't show them anywhere I can find. If I use those then do I still use the bearing shield on either side? If I do, it seems they don't sit flush with the frame (though I haven't tigthened down the non-drive side as I thought I'd ask here first.

For reference: http://www.sram.com/_media/techdocs/95-6115-002-000.pdf

Part #4 is the bearing shield that has printed 30 mm spindle.


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## cxwrench (Nov 9, 2004)

bike867 said:


> I have the little retaining clips installed in the grooves in the bb shell. Then I've pressed in the outer bearings using the park adapters and the headset press tool (one side at a time). After doing so, the outside face of the bearing is roughly 50 mm from the outside edge of the bb shell. Included with the bb are two black aluminum spacers that are 50 mm wide and the little crib sheet included with those say that for 72 mm shell to not use them, but for a 68 mm shell (mine is 68 mm) to use them. The Sram website doesn't show them anywhere I can find. If I use those then do I still use the bearing shield on either side? If I do, it seems they don't sit flush with the frame (though I haven't tigthened down the non-drive side as I thought I'd ask here first.
> 
> For reference: http://www.sram.com/_media/techdocs/95-6115-002-000.pdf
> 
> Part #4 is the bearing shield that has printed 30 mm spindle.


not really sure what is going on here, other than you are not measuring correctly. there is no way your bearing is 50mm from the edge of the bb shell. maybe 5.0, but not 50. assuming it's 5.0mm, i'd guess you'd be using the spacers...but i've never seen those before. every one i've worked on looks exactly like the techdoc drawing, they had the wavy washer, shims, shields. you may want to call sram and talk to someone, they're really good w/ support.


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## bike867 (Feb 2, 2011)

cxwrench said:


> not really sure what is going on here, other than you are not measuring correctly. there is no way your bearing is 50mm from the edge of the bb shell. maybe 5.0, but not 50. assuming it's 5.0mm, i'd guess you'd be using the spacers...but i've never seen those before. every one i've worked on looks exactly like the techdoc drawing, they had the wavy washer, shims, shields. you may want to call sram and talk to someone, they're really good w/ support.


Yes, sorry, that would be 5mm, not 50mm. Should the bearings be recessed into the bb shell that much or do most frames have the outside face of the bearing nearly flush with the outside? I can snap a photo of the little rings and the crib sheet that came with them. I'll see about calling Sram and I can add some photos to this discussion if it'd help.

[update] Just called SRAM. They are closed today for "snowmageddon". Direct quote from their automated message.


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## aengbretson (Sep 17, 2009)

Yes the bearings' outer face should be slightly recessed compared to the BB shell. When I look at my BB30 setup (although I'm using a Cannondale crank) the bearing shields are almost dead flush with the edges of the BB. I don't know if the shields account for 5 mm, but as long as the bearings are properly installed then there probably isn't a problem...


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## bike867 (Feb 2, 2011)

Here's the crib sheet and a post regarding the use of these spacers:

http://glorycycles.blogspot.com/2010/02/sram-and-truvative-crank-compatibility.html

My general question is: If using the Sram Red compact crankset, a Sram BB30 bottom bracket, and a 68mm shell width, do you use these spacers? I can't find documentation that says either way. Also, do you also use the bearing shield with the spacers? This post is from Feb 2010, so surely people have run into this?


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## roadboy (Apr 1, 2003)

You do not use those spacers, they are intended for mtb BB30 setups where a 68mm shell is used. All mtb cranks are designed around a 73mm shell, so if you had a 68mm shell then you need to use the spacers (2.5mm) each to take up the extra 5mm of space. All road bb30 cranks are designed around a 68mm shell width and the spacers are not needed when installing a road crank in a road frame with a 68mm bb shell width.


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## bike867 (Feb 2, 2011)

Thanks for the information, very helpful. Should the bearing shields be in contact with the bearing? My bearings are now that 2.5mm inside the bb shell touching the bearing retaining clips, so they obviously won't in my case. Seems like I'll have a 2.5 mm gap between the bearing shields and the bearings...I'm guessing that is normal?


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## Shuke (Oct 27, 2009)

Does anybody know how many plastic spacers are required before the wavy washer on the non-drive side of a 2010 caad10 with a bb30 red crankset?


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## frdfandc (Nov 27, 2007)

According to Srams tech doc on page 26, it shows 3 spacers before the wavy washer.

http://www.sram.com/_media/pdf/sram/dealers/MY10-SRAM-Tech-Manual-Rev-A.pdf


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## Shuke (Oct 27, 2009)

Right but it also says that the number of plastic spacers will vary depending on your frame. Something like "if you tighten the crankset and the wavy washer is fully compressed then add spacers until it isn't" I saw a post where somebody with a CAAD9 only had one. I'll start from there.


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## ZoSoSwiM (Mar 7, 2008)

The black SRAM bearing shields on my supersix are exactly flush with the BB shell.


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## aengbretson (Sep 17, 2009)

Shuke: the number of spacers is not "set" - if everything is very close to spec then 3 should do it. Sometimes you need more, sometimes you need less. 0.5mm is 0.02" (although ±20 thou is a rather loose manufacturing tolerance). Better to have too few than too many spacers, lest you overload the bearings. The purpose of the spacers and wave washer is to set the bearing preload at an acceptable level. Start with 3, check to see if you can slip an extra spacer into the gap formed by the wave washer when everything is torqued to the proper numbers. If it is easy to do so, then pull it apart and install the spacer, torque it down, and check again.


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## PoorCyclist (Oct 14, 2010)

My wave washer is sitting in 2mm space, it is on the large end of FSA spec, still plenty of preload. I don't notice any problems like chain falling off, 
if I yank the crank arms sideways hard enough I suppose there are some flex, but in actual riding no problem..
I read some people try to make it almost flat but I don't see the point..
but you would need different amount of spacers depends on the frame.


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## ZoSoSwiM (Mar 7, 2008)

When I installed my Force cranks I went from 3, to 2, down to only 1 spacer. Cranks spin smoothly and they don't move side to side at all. I can see a slight wave in the wave washer still so I suppose it's all set. Plus I have a new set of backup bearings so I'm not too worried about them.


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## bike867 (Feb 2, 2011)

Ok, I have it all clamped down. Thanks to all. I'm running one clear plastic spacer and there is a slight wave to the wavy washer when spinning the crank and tightened down to about 51 Nm. There is a little drag on the crank now that is is all snugged up, but I've seen others complain initially until they ride it a few 100 miles.


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## PoorCyclist (Oct 14, 2010)

Got a question for you guys,
the wave spring washer sits against the spacer or bearing shield if you are not using spacer.

The washer spins with the crank arm, and spins bearing shield with it, at least it seems the bearing shield spins also? How does that work...? How can the bearing shield spin like that.


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## bike867 (Feb 2, 2011)

I believe that the bearing shield is in contact with the inner race of the bearing. So, nothing is really rubbing per se and so it isn't a problem. The wavy washer (and any spacers) along with the bearing shield spin with the crank. I didn't actually look at it, but that's what I would expect to see. If the bearing shield did not rotate with the crank, the wavy washer would tear into it pretty quickly.


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## hummina shadeeba (Oct 15, 2009)

*uuggghhh*

those plastic spacers? I can't believe the rediculousness of installing bb30 cranks. I can't even figure out the large metal ones. Please help me.
I have a 68mm shell. I just cranked the cranks down without any spacers and all was seemingly fine. All tight. Spun.
I didn't like the idea of adding the spacers if they weren't necessary.
6 months later after some ticking that would go away my left arm has a bit of play. 
yesterday shop put new bearings in. Picked it up and was handed two spacers and a much simpler installation chart simply stating 68mm shells needed them. I tried to put them on and there was almost no resistance and I bottomed out with the wavy washer flat. Took them off and, back together, It was tight and span round so I rode it. Now it's all loose. Much more so than before.


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