>>1135638>. Bike tech of 1917 vs 2017 is cave man tech, to cave man with carbon fiber ergonomics. Cars have improved exponentially in comparisonLol dude, they were still racing road on singlespeeds back in the 1919.
This is the TDF winning bike from 1948. You move the chain with one rod, and the other rod releases the axle and then you move the wheel in the dropouts, which are notched, to get chain tension.
That is nothing like a modern bike. It is archaic technology.
Derailer gears and something resembling a modern bike didn't really come in until the 50s.
Indexing in the 80s and integrated shifting in the 90s were improvements much akin to fuel injection.
Greater gear range, less weight, aerodynamics and much better braking, make modern bikes quite a lot faster as well, but those changes aren't fundamental. By the 70s, bicycles were well refined, quite reliable and more or less as nice to ride as they are now. That's true for cars as well. An Alfasud is just as much fun to drive (quite a lot more really) as anything you could get now.