VOL. 51 ISSUE 33 AUGUST 19, 2014 P81
engineer Joseph Barter back in
1905 in producing his Fée Fairy
motorcycle, which worked so
well that he was hired by Doug-
las to produce a similar design
to power a new range of motor-
cycles as well as aircraft. Ironi-
cally those saw action during
WWI against those powered by
the later rival BMW engine.
This longitudinal format de-
livered the same smooth run-
ning and lack of vibration that
the BMW flat-twins are famous
for today, which also led to im-
proved reliability back in those
early days of primitive materials.
And the low build of such bikes
not only produced improved
aerodynamics, but also better
handling over the bumpy road
surfaces back then, thanks to
the low center of gravity.
Harley-Davidson was only one
of many companies to produce
such a bike, the early-1920s
600cc XF model of which only a
handful were made. Interestingly,
Harley later copied the BMW
format in producing the equally
short-lived XA Boxer twin in 1941
for the U.S. Army, which had
specified shaft drive.
But the success of the flat-twin
Douglas in dominating 1920s
sprint racing in the UK, as well as
being the model of choice for the
early days of speedway racing
and a successful Grand Prix-win-
ning road racer, in turn led to its
downfall. As engine performance
increased, so did the problems
of countering the extra heat this
produced, and especially in cool-
ing the rear cylinder.
Thus the flat-twin motorcycle
with lengthways cylinders died
a death in the 1930s, and Doug-
las itself copied the BMW format
with the launch of its Endeavour
model in 1934.
But now the 47-year-old Midy
has brought the same length-
ways flat-twin format back to
the marketplace 80 years later,
but in a unique way. For the first
time ever, he's done so by liquid-
cooling the engine to deal with
the problem of the rear cylinder
overheating, and also by rotating
the front cylinder downwards and
the rear upwards by 25 degrees,
in order to hold down the wheel-
base to a manageable 59 inches.
He's also been able to retain an
acceptably balanced 49/51 per-
cent weight distribution.
In doing so he's been able
to produce a motorcycle that is
completely unique, at whatever
price tag, but also to overcome
BMW's problems with the length-
ways crank's sideways rotation.
And also any ground clearance
issues with the sticking-out cylin-
ders on today's grippy tires – one
reason BMW canned the proto-
type R1 desmo Superbike it built
20 years ago, but never raced.
The Midual engine, designed
by Midy himself, is a DOHC eight-
valve flat-twin with vertically-split
crankcases, with its cylinders
tilted forward by 25 degrees to
provide space for the six-speed
transmission to be mounted under
the rear pot - combined with an
oil-bath ramp-style slipper clutch,
and straight-cut primary gears.
According to its creator, the
reason for the dry sump format -
with the oil tank positioned above
the engine - is to counter poten-
The Midual is a true monocoque
with the frame housing the fuel.
Company owner and bike designer
Olivier Midy has already taken de-
posits for two of the Type 1s.
