1901 Pierce Pan American Special
It's not just bikes that can be classics... the problems that bike designs try to fix can be classics too! In the case of the Pan American Special, those problems are the need for a clean, trouble-free drivetrain, and rough roads that call for a suspension system. This bike avoided the problems of chains by using an enclosed drive shaft. Of course, drive shafts have their own issues, which has led to them not being popular. The suspension system on this bike includes small leaf springs in the fork, and a coil spring inline with the seatstays. Other than a lack of damping, this seems like a reasonable implementation.
Steve in Peoria