A chainless bicycle can be the answer to a cyclist prayer and may be a sign of things to come. The chain that is used on a conventional bike is replaced by a innovatively designed, fully enclosed, drive shaft from the pedal crank shaft to a set of gears on the rear hub.
You get all of the fun without the chain!
And, since the drive shaft is self contained and protected from the elements there is no more greasy or torn clothing and almost zero maintenance. And, best of all, the less time spent on maintenance means the more time you have for riding.
This is one reason why older riders as well as bike rental stores are finding chainless bikes a smooth and quiet ride and an exciting alternative to a conventional chain driven bike.
Purists aren't big fans of chainless bikes since there is a small reduction in pedaling efficiency and they don't offer the wide range of gears that a conventional bike does. But most boomers don't give a hoot and are tickled to have a trouble free ride.
Any complaints that I've heard generally come from rather aggressive, off road, riders and usually referenced the relative difference in pedaling efficiency ( which no one can really quantify ) or the fact that it is a bit more difficult to change the rear tire.
If you are planning to ride on very hilly terrain a chainless bike would not be the best choice but for casual riding on mostly flat terrain it could be a great alternative.