Singlespeed & Fixed Gear - Chainline issues with Truvativ Omniums?

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whitekimchee
11-06-09, 11:47 AM
I was about to pull the trigger on a Truvativ omnium crankset. However, i did some research and found that some people were having problems achieving a straight chainline. From what I read, the Omniums use a 41mm chainline and the traditional track chainline is what? 42? (correct me if i'm wrong). I apologize about reviving a tired subject, but I need more answers.

I currently ride a Bianchi Pista with a rear wheel setup that has Dura Ace 7600 hubs (44mm) with a EAI cog. I know having a chainline that's off by 1 or 2 mm is not that big of a deal, but I'm OCD about things being straight.

Would my setup not be compatible with omniums?

Yo!
11-06-09, 12:54 PM
I originally bought Omniums to work with one of my Panasonics, and I wasn't able to make it happen.

First of all, the spider is super burly and I was not able to completely seat the crank before interference with the chainstay occurred.

Secondly, even with the crank arm seated, my chainline was really out of whack; I was using a formula hub, which advertises a 36mm chainline, which is super tight. My frame supports a 41mm chainline, so even if I got it all said and done I was looking at about a 4-6mm difference, which is way too much for my comfort.

I eventually returned them and got a SG75 bb with a 109mm spindle.

I think these cranks are badass, but probably better suited for newer frames. I think that they should probably work out with your Pista. My advice is to search velospace for dudes running omniums on their pista's, get the rear hub info, and there you have your answer.
adriano
11-06-09, 12:58 PM
dont sweat it.

brandonspeck
11-06-09, 02:01 PM
sounds like you should be fine. I knew a guy who had that same setup and he was fine.
das_pyrate
11-06-09, 05:30 PM
omniums have a 44mm chainline iirc
gospastic
11-06-09, 05:53 PM
You recall wrong.
whitekimchee
11-06-09, 06:47 PM
who's wrong me or das pyrate?
the_don
11-06-09, 07:20 PM
Here is one!

http://velospace.org/node/19277

http://velospace.org/files/bianchi_pista.jpg
whitekimchee
11-06-09, 07:21 PM
yeah i found that one too. i pmed the dude, awaiting his response. thanks don.
Severian
11-06-09, 08:37 PM
I have an Omnium that runs back to a Surly track cog mounted on a Phil Wood. I have no problems with chainline.
Soil_Sampler
11-06-09, 08:42 PM
http://www.sheldonbrown.com/chainline.html
muffdoc
11-06-09, 08:52 PM
I have them on my pista. No difference from stock. I'm running them with a set of Bontrager Wheels, the ones with the low spoke count(20f, 24b).


just measured it and I'm getting 42mm.