Endless Rotation with Hinge?

Hello,

I`m new to ODE and expeditiously run into trouble.
My problem: I want to realize something like a simple 
endless rotation (like a gear, but without steering like 
in the buggy examnple). As far as I know, the hinge joint 
must have angles between -pi and pi. Is it possible to 
override these constraints for a hinge? Or maybe there is 
another simple solution for my problem?

Thanks in advance,
Rene