I would love a shaft drive on my bike, but maybe I'm a little lazy. I can see wanting a traditional style Bonnie keeping the chain. If it has a shaft and is 1500, why not just have it a different moniker. In my stinky opinion a 1500 America/Speedmaster should have a shaft drive. In fact, I'd get a belt conversion if I could afford one. Just cause I tend to forget to lub it often enough. (bad me)