[Chuck Moreland]

I recall my university physics prof talking about this system ca 1982. It wasn't ABS exactly, but a system that ensured the front brakes would lock up before the rear brakes.

I'm not sure how the system functioned, but the prof had a rigged up a cool demo to prove the concept worked.

Of course he first asked for a show of hands; would it be better to lock up the front brakes first, or the rear? Most students said locking the rear would be better (who hadn't locked up the rear wheel on a coaster brake bike. Put's down a cool skid-mark).

The prof did then perform the demonstration using a toy car rolling down a ramp.

Firstly locking only the rear brakes, the car did loops as it slid down the ramp.

Secondly locking only the front brakes, the car tracked straight and true down the ramp.

A very instructive lesson that I've reflected on many times over the years.