Singlespeed & Fixed Gear - Losing sleep over my SRAM Omniums

Its been a while since I have posted anything... but I know this forum is full of priceless information- and right now I need some of that...

I putting together a track bike and purchased some SRAM Omnium cranks and BB. I installed the BB no problem but am having some trouble with the cranks.

I can line everything up just fine, but when I go to tighten my crank arm down to the spindle I am getting about 2mm of play (at least). As per the instructions, I have greased, and re-greased.

However, as I was laying in my bed trying to figure out the problem I realized that it may be my tools. I am using a "multi-tool"; the kind that has maybe 4 hex wrenches, along with a screwdriver, etc. The length of the tools are around 4 inches.

The required torque to tighten the cranks is around 55 Nm (or 155 pounds per inch).

Could it be that my multi-tool wont give me that much torque without feeling like its going to shatter?

I am planning in taking it to a bike shop tomorrow. But would like to know anyone's thoughts on this... as I am losing sleep over it!

Thanks...

No matter how hard I tried to tighten them I had the same amount of play on both my S300's and Omniums. I gave up and rode them both for months with no problems.

Take it to the shop and ask them which tool you need to do the job correctly.

3 problems solved:
- Your crank situation
- Your confidence
- Your bike mechanicing knowledge

Did you use the proper BB installation tool?

I'd also use a torque wrench.

Oh and go to your favorite hardware store and buy a set of long metric allen wrenches ($10?). You will find them very useful over several years...even with IKEA furniture....especially with IKEA furniture.

Ikea makes there own allen set now :\ my bed has 5.3 mm allen its not standard or metric, but anways carelton is right, a couple of long metric allen's will be better when ur multitool, plus u need the torque

My bed uses standard 3/4" bolts because it was made in america.

Oh and go to your favorite hardware store and buy a set of long metric allen wrenches ($10?). You will find them very useful over several years...even with IKEA furniture....especially with IKEA furniture.

Amen to this. Go to harbor freight and buy two sets for about $20. You're going to lose your 6 and 5mm ones non stop so it's nice to have an extra set.


My bed uses standard 3/4" bolts because it was made in america.
Thomson bed?

Thomson bed?

My mattress covers some of the bedpost, so Thomso or Homson depending on which side you're looking.

i will tell you that GXP based cranksets do require a lot of torque to be tightened correctly, i doubt you could generate enough to tighten them properly with a small multi-tool. the other issue, which i will mention over and over is that the BB shell needs to be prepped properly, i doubt it's your problem here, but the shell should be faced, or at least ensure that the mating surface is free of paint, flat and at a 90* angle. also, of course, the bb shell width must be correct and within tolerance.

as carleton mentioned - go to a LBS.

No matter how hard I tried to tighten them I had the same amount of play on both my S300's and Omniums. I gave up and rode them both for months with no problems.

I built my entire bike with a multi tool. I rode it for months with no problems.











But one day everything fell apart.

I've put a handful of bikes together with my multitool, including GXP cranks on a few. It definitely takes a good amount of torque, maybe even a little ham-fisting, when installing for the first time.



Ham-fisting sounds really gross. Sorry.

McHam-fist

Sounds like something that would sell big at Mcdonalds.

As others have said, you are never going to get enough torque to properly install Omniums with a multi tool and I seriously doubt you'll even get enough using a standard allen wrench (which is most likely why so many people have "problems" installing them).

You don't necessarily need to use a torque wrench because you will be able to feel when there is no more play from side to side but get yourself an 8mm allen socket (1/2" drive) and use a ratchet or breaker bar.

I purchased an 11$ parktool that had an 8mm hex wrench on it. problem solved. thanks everyone...