Buy a cheap track/SS wheelsset...nashbar, nycb what ever (cheap)...find a 70-80's road bike with semi horizontadropouts/ brake drillings..forget the chain tensioners adapt your chain line by finding a suitable bb to adapt the cranks or run the inboard ring and use little cog for a fixed..or make it neat and run the out board ring on a double and switch to a different BB based on the results of some preliminary measurements...set it up make sure your teeth width match with your chain, set up a brake if you like...(use it only when you need it if you like burly,,,or use it all time if you knees bug you)...be brave and kick some butt working you spin and becoming an improved rider. good look at the chain line thread in this forum for a few complicated solution for chainline solutions...i'm buzzed out