Omnium bottom bracket help.
 

So I threw a Miche Advanced crankset on my Dodici Special when building it up because I already had it lying around.
The 107mm Miche BB that it came with was too short (cranks hit)
Threw a Shimano 110mm in there and it clears by maybe 1.5mm now

That is all good, except my the chainring is not round...at all.
I picked up a cheap FSA chainring to throw on there but I really want to throw some Omniums on there.

Will the GXP BB that comes with the Omniums work or will the cranks be hitting the chain stays?

They should fit; here's one with a pair fitted

http://farm6.static.flickr.com/5222/...557db50b_b.jpg

I came across that photo, but that is a different frame then I have

On BikeIsland it says it with not work with bikes needing a spindle length longer than 107-108mm
If a 110 barely clears now, I'm thinking this will be a no go

Does anyone else make a GXP bottom bracket in different spindle lengths?

This guy runs them, but also runs a Chris King GXP (doesn't say spindle length)
http://velospace.org/files/Dodici_Sp...hackamole1.jpg

The spindle is integrated into the crank arm, so I don't think it's variable. I've read about people using spacers to space out the BB, but I'm not sure if this is advisable or what. Just some ideas for you to chew on.

I'm having an issue removing the left crank arm. I didn't have the L shaped allen wrench for leverage so I picked one up and still can't get it off. Might've overcompensated how much I tightened it after it ended up being loose last time. any suggestions that don't involve brute force?

So I ended up buying the Omnioms and the don't fit.

There's pretty much nothing you can do to space it out right?

Doesn't make sense because I talked the a few dodici owners and they all said it would work

Where does it not fit? Pic?

Both the chainring and crank arms hit the chainstay.

I think I got a defective frame?

This makes absolutely no sense. Wouldn't a longer spindle offer more clearance? And since when is spindle length determined by the bike and not the crankset being used?

same with my special
 

Hey Guys,

I know this thread hasn't been used for a while but I have pretty much the same problem. When I first got the Omnium I realised that in extreme Situations, I could hear a loud clicking noise because the Crank hit the Frame and damaged at least the paint (not the arm but where the chainring is mounted on). So I went to my bike shop and we decided to put two spacers on that same side because with one it was still hitting the frame. The chain line was still ok so I decided to go with it and it was fine for a few weeks. Now I realised, that it doesn't turn as smooth as it should anymore (when spun around it stops after a only few turns) and with the Crankset unmounted I can feel that the bearing is not turning smoothly at all. Could the two spacers be responsible for that? How did you end up solving the Problem chrissss? Should I bother just trying a new BB or is it definitely going to happen again?

Thanks a lot in advance

Whoever installed those spacers should hang up his wrenches and go work at Dunkin' Donuts.

Using spacers on a GXP bottom bracket may seem to solve a clearance issue but - because the spindle attached to the drive side crank arm doesn't magically grow when you add spacers - it also means you need to over-tighten the non-drive side crank arm bolt to get the crank arm to fully seat on the spindle, which in turn crushes the bearings.

Essentially, your "mechanic" ruined your bottom bracket. Go back to the shop and kick him in the nuts.

OK thanks Scrodzilla, thats what I feared! So now I need a new bottom bracket and I'm back to the original problem of the thread...

Omniums have very well-known clearance issues with some frames, especially aluminum frames that have thicker stays that aren't dimpled (although I've encountered a few steel frames that didn't get along with Omniums either).

It's probably not what you want to hear but you're not going to be able to use them on whatever frame you have. Sell them and start shopping for another crankset.

And please post a video of you kicking that guy in the nuts.

Haha well I actually like going there because he's a nice guy but I'm definitely going to talk to him about that.

Thanks for your brutal honesty. I hope I'll find a setup I like.

Whats still bugging me though is that pretty much 90% of the dodici special frames you can find online have the omnium. Don't they ride theirs properly? I don't get it...

Is it the spider or the crank arms that hit the frame?

Some variable that could explain why some work and some dont:

crank arm length

frame size

assuming it is barely hitting:

differences in production batches

tolerances of frame construction

tolerances in tubing production