So the freewheel (dicta) on my Van Dessel flip-flop sits out a good bit further than the track cog (dura ace) so I put a 40 t on the outside of my road double (sugino) and a 42 on the inside.

This gives me a 42x16 fixed and 40x17 free and the chainline looks good (better fixed than free, but seems ok for both), at least to my very untrained eye.

Is there any reason not to run this setup? it rode fine both ways for a quick trip up and down the alley, but I'd rather be sure it will be ok before I go off and kill myself on a long ride.

Thoughts?