Track cogs have right hand threads, just like freewheels. It's the lockrings that have left hand threads. Regular freewheels have the same thread size a fixed cogs (1.375" x 24 tpi), but there are some smaller BMX freewheels that have 30mm x 1mm threads.
__________________
What, Me Worry? - Alfred E. Neuman
I'd like to think i have as much money as brains.
I see the light at the end of the tunnel, but the tunnel keeps getting longer - me