I went to BikesDirect.com and looked at the Kilo OS. The version they sell has brakes front and rear and costs $450. The 5 speed version cost $480.

These are being discussed as fixed gear bikes but I think the multi-speed Sturmey-Archer hubs freewheel. Am I incorrect about that. The fixed gear OS (old school) bike has a single fixed gear.

Now, a five speed, internally geard hub has some appeal to me. Are there any restrictions on the external gear ratios one can use without breaking the hub? It comes set up as a 48 X 16T. Is it allowable and are the parts available (chainwheels and/or rear cogs) to lower the gear ratios?