On the subject of the "EARLES FORK"
The Earles fork is a variety of leading link fork where the pivot point is situated behind the rear of the front wheel, and this is the basis of a patent for the design.
Conceived and designed by englishman Ernest Richard George Earles.
When braking hard, the triangulated fork actually causes the front end of a motorcycle to rise!
which is the opposite to the action of a "telescopic" fork.
In December 1951 Earles applied for a patent on "motor cycle front wheel forks"
The greatest benefit of an Earles fork is in sidecar use, with its adjustability for rake and trail.
BMW motorcycles exclusivley used the Earles fork, between 1955 & 1969
despite the fact that most would be only used as solo motocycles.
Some handcrafted "variations" of leading-link fork suspension
The swinging arm pivot has two positions: moving it to the forward position reduces trail, allowing the bike to turn with less effort when a sidecar is attached.
Generally speaking, leading link (Earles) forks have less rake and trail than telescopic forks,
and tend to be more rigid than their slider counterparts,
thus maintaining their geometry during cornering and pothole encounters.
Telescopic forks actually turn easier during low speed maneuvers,
but for rough roads the Earles Forks are by far the best choice.
Earls Court London, hosted many an exhibition but no connection to the Earles Fork!