First man to use disc brakes on 2 wheels ?

First man to use disc brakes on motorcycle :?:

hello lionel well as you see my name is Dixon does that ring any bells , Well my father was an engineer and a boiler inspector and he was freind with Denis Parkinson and his dad Bill Parkinson there Garage and sales room was at Ings Road Wakefield ,And there My great Uncle Freddie Dixon he was a Pionneer of motorcycles and car racing He was the frist man to use Disc Brakes in 1923,
from;

http://www.nortonownersclub.org/noc-cha ... /958198253

https://en.wikipedia.org/wiki/Freddie_Dixon

Actually, Douglas's Engineer Les Bailey is credited with being behind the RA (Research Association) disk brakes
as offered on the Douglas for 1923. But he would have been part of a team, and Freddy Dixon was in there as rider,
and the whole story is a bit fuzzy, so Anna may be right - always worth checking anything she quotes.
The brake was cable operated too, not hydraulic.

Scabbed off the Douglas Forum

Note the spokes on the 'disk' !!

Its worth commenting also that bikes going back into the dark ages before that had a wedge of brake friction material
that operated on a V in a large pulley as a back brake, so the distinction of what makes a disk brake a disk brake
maybe needs some careful definition. My 1910 Triumph belt drive (project) has such a rear brake, and it was very well developed by then.
Bicycle type brakes with a caliper squeezing or pulling two rubber blocks onto the front rim had been around even longer then too,
so the rudimentary ideas for a disk brake as we know it had been circling around for a while...

Disk brakes reappeared in the 1950s ? in racing, anyone know who re-pioneered them again, if I can use that term ?
Jags had them on their LeMans cars, were they the first ?
They would have been hydraulically operated - which itself was an idea taken from aircraft use ??
Harleys had a hydraulically operated rear 'juice' brake - late 1940s was it, or 1950s after Jag ?

As Rohan said, my understanding was that following aircraft experience Jaguar were first (if you believe their propaganda!) to use disc brakes on a car, for their Le Mans racing cars. It certainly gave them a big edge over the main competition, Ferrari. According to Wikipedia, so it must be true, the first use was on the 1952 C Types on all four wheels.
cheers
wakeup