SRAM Omnium crankset

Some updates!

Bike24 replied to my inquiry and said that they sent me the right model (Sram road), which apparently doesn't come with spacers (hmmmmmm) ["Road bike BBs usually don't come with spacers"].

Okay, so I visited two bike shops and both said that this particular CK BB would not fit my Sram Omnium, as I have play/clearance in any direction on the NONDRIVESIDE. Basically just as if you'd try to use the CK Shimano BB with a TAPERED Sram spindle: it won't work! Both also believed that this wouldn't even be the "Sram road" version... Because my CK BB also lacks this typical Sram tooth cap: http://r2-bike.com/bilder/produkte/gross/Truvativ-SRAM-GXP-Specialized-OSBB.jpg I mean, the Omnium stock BB has that and it fits on the spindle perfectly on the NONDRIVESIDE.

I think I need a CK BB which comes at least with this toothcap... as an indicator that it could work out :D
Not even sure if I can return my CK BB now as it has some visible marks left from the installation & deinstallation (using my old stock BB again ... for now) -_____-

Basic Road BB comes plain i guess.. You need stepped axle road BB from Chris King to fit Omniums. Lazy to upload pic.. fitted mine CK stepped axle bb to omniums today.. left out the adaptor washer for the non drive side (was shown on installation guide) as it made crank spider touch chainstay..so without it bb fitted perfectly nice and tight.

Can somebody please help me, my omniums don't seem to be spinning that well, but the bearings appear to be in good condition...this only happens when they are installed on the bike and everything is tightened up. I really don't know how to explain it properly, but it seems to actually take some real effort. Also, they stop spinning quickly, my chain isn't too tight, etc, never had problems with cranks before, might just go back to campagnolo

BB shell might need facing

Have a look back through the thread - Arup had the same issue.

If you haven't had the frame faced, as above, that's a good start.

External BB cranks don't tend to spin like cartridge BBs when unloaded. But if its actually binding up something is quite wrong.

Btw,
just wanna say that you guys were right and I'm now running my CK BB with the Omniums by using the CK adapter kit #7 (http://chrisking.com/bbconversionkits).
So that works fine! :D

Hovis

To be honest, I've never used a torque wrench with all my GXP cranks. I just keep tightening >until play is no longer detectable, and then tighten a bit more.

I experienced play but kept a cool head, and gradually tightened one revolution at a time until it was gone. Realised I'd left off one of the seal caps so removed the crank and started again. After only a couple of turns I heard a horrible crack. Now the cranks feel tight (no play) but the crank bolt just spins so I'm worried about what damage I've done and how I can go about removing the cranks to replace BB in future.

Anyone had any experience with this? Is it safe to ride into work with a view to dropping it off at a nearby shop for a professional look and pre-emptive replacement of nackered bit(s)?

Ooops. Remove the extractor bolt - it sits on top of the crank bolt - then see if you can pull the crank bolt out. Then you'll get an idea as to what has happened.

If the bolt isn't engaging riding it will damage the axle interference fit with the crank arm - and the arm may even fall off.

Why why why didn't I just buy a torque wrench?

Because you don't need one. I've no idea what you've done, but I doubt a torque wrench would have saved you.

I'm stumped. The only thing I could think was that I had over tightened. Gonna be really hard to sit around and not obsess.

If you used a cheater bar about two foot long and put all your weight into it then maybe, yeh.

But that would be crazy.

Or maybe he has @ChainBreaker arms

Never seen Chainbreaker's arms but it seems it seems the crank bolt is cracked and I'm in the frame. Desperately seeking a replacement but, unsuprisingly, there are none about and the UK distributor is keeping everyone waiting.

The head snapped off? You beast ;)

Does anyone know if the 11.6900.002.160 is the right bolt? And can I get one from anywhere other than SRAM?

I think it's M15×1.0 like most ISIS, Octalink and some HT2 crank bolts, so it might be worth offering one of those up to the problem to see if it will hold your crank on while you wait for the proper SRAM one which is matched to the cap to provide the self-extraction feature.

The guy at Action Bikes seemed to think it's an "absolutely crazy" size, and suggested that other crank specific bolts won't fit. I was just being impatient and hoping someone had already done all this leg work so I could drop the bolt off and have done with it. I guess I'll have to wait until lunchtime to get the bolt and run it by an expert after work. Hopefully they can tell me definitively and I can get something in time to be riding next week.

Walk in to Evans. Buy any SRAM GXP crank. Accidentally remove the crank bolt. Return crank to Evans for refund*

• I'm not actually recommending you do this. Not at all. No. And I'm only assuming that GXP cranks have the same bolt, I've no evidence / experience to suggest they do.
  
  

Actually, you could probably borrow a bolt from someone on here - there's got to be someone who has a gxp crank kicking around who could lend.

Blue Door Cycles of Crystal Palace sorted me out in timely fashion and Action Bikes did the fitting as they already had my bike. I did over tighten and I will be investing in a torque wrench sharpish.

In the meantime I'm zipping through traffic giving it om nom nom nom like Cookie Monster.

I was just re-installing my omnomnoms and have done the exact same thing I think. Felt about 1mm play so tightened again and then a crack sound and now a free spinning 8mm bolt. @beanpie did you source the replacement crank bolt from blue door cycles? was it just a case of getting the old 5/8" and 8mm ones out and replacing with a new set?

Snapped a chainring bolt on my Omnoms yesterday, crap aluminium! Been linked to these steel Truvativ replacements, I've read that due to the thickness of the crank spider and chainring they need double chainring bolts. Is this correct, or would I need to space them?

I was linked to these in the HHSB thread http://www.edinburghbicycle.com/products/truvativ-chainring-bolt-kit

Guys please, need your help
I bought second-hand Omniums. Problem is, that they have little bit of play. I tried to put spacers between frame and BB, and that didn't work, I also don't think I could tighten 'em more...
Next thing I'm planning is to put new BB, but i don't want to spend $$ if it's not gonna help me. Any advices, anyone had problem with play on Omniums?

@Shl

It sounds like the play comes from knackered bearings since frame spacers did not help.

The GXP BB don't last long so I would advise replacing it first - they are £20 new.

They need a fair bit of torque to remove the play. I believe around 50Nm.

Grease and tighten. If there's play remove and repeat. Worked for me, but mines were new