no biggie, man. in future, you might want to do a search of the site before posting on the site. We get a few recurring threads, and no offense, but this is one of them, along with the questions about the landrider bike.

IMHO, I think that the driveshaft would work for a city type of commuter bike, like what is popular in europe, but not for a roadie bike. in order to make the driveshaft stiff enough to take the power of a sprinting racer, you'd have to make it fairly heavy, and that would defeat the purpose. a chain, for all of its faults, is fairly light.