>>>mechanic<<<

>>>uses Biopace on FG<<<<

If set up properly, and by that I mean having a straight chain line and proper tension, there is nothing wrong with running a BP chain ring on a fixed gear.

Setting the chain tension on a BP equipped bike is no harder than setting up the tension on a non BP equipped bike... you always have to find the point where the chain is tightest and then back it off just a wee bit. You do not want to have too much sag on a BP equipped bike as if this happens you could throw the chain.

My Kuwie with a 38 tooth Biopace ring, 16 tooth rear cog, and for good measure, a U brake in the rear (which I have since removed).

I rode the BP ring until it wore out with not a single problem and am now running a 40 tooth Sugino (round) as I wanted a little higher gearing. We're talking about 1000's upon 1000's of km.