distributor and oil pump were all driven by shaft and helical
gears. The generator was horizontally mounted in front of the
crankcase, its shaft driven by a jackshaft off the crank. The dis-
tributor was vertically mounted behind the cylinders, taking its
drive from the same jackshaft that drove the generator. In the
same line as the distributor, a shaft ran down to the oil pump
mounted at the bottom of the sump. Oil was kept in the crank-
case, rather than in a separate oil tank.
All this was fairly innovative, but perhaps the most fasci-
nating feature was the valve
actuation mechanism. Cam
drive was via two large gears,
one above the other and
driven from a gear on the
crankshaft between the cyl-
inders. The top gear featured
a single cam lobe on either
side, against which lever fol-
lowers operated short valve
actuating pushrods that
were parallel in one plane to
the valves, set at a 90-degree
included angle in the hemi-
spherical cylinder head com-
bustion chamber. The push-
rods were very short and
therefore light and strong.
All this may sound quite
revolutionary, but elements
of this design had already
been seen in radial aircraft
engines. A vaguely similar
system had also appeared on the Parilla 175 in 1953.
The twin was well received by show attendees. MV claimed
its power output was around 20 horsepower, some 7 horse-
power more than its Gilera rival. It also looked like it had just
come off the race track. Twin carburetors, cylinders inclined
45 degrees forward, beautiful swooping exhausts and gener-
ous radial fins in the heads screamed performance. Even the
Earles forks had been developed specifically for this model.
Too much bike
Sadly, Carlo Gianini’s feat of engineering was a dead end
for MV. Only the prototype was built, as Count Agusta realized
it would have been way too expensive to put into production
and sell as an affordable road bike.
“The MV300B contains design elements unusual but not
unheard of at the time,” says Ian “Gowie” Gowanloch, founder
of international parts business Ital-Spares. “I owned a Gilera
B300 when I was living in Italy. It was without doubt one of
the most inelegant pieces of
design I have ever seen. That
the MV 300B was conceived
as competition seems incred-
ible; they are opposite ends of
the spectrum.
“The MV 300B is different
from normal everywhere you
look. It is also immediately
obvious why the basic ele-
ments have not been cop-
ied. Very little of the exercise
is simple and cost effective,
either to manufacture or
assemble.”
Technically, it left Gilera’s
twin in the shade, but its
ultimate failure was its over-
design. It was simply too
much technology; too com-
plicated to tool up for a ded-
icated production line and
too difficult for non-special-
ist mechanics to maintain. And so the prototype was pushed
aside and forgotten.
However, development of a racing version was started. This
also was ahead of its time, with a tubular triangulated space
frame inspired by contemporary F1 car Grand Prix chassis
design. It was another brave attempt, but MV decided it would
be uncompetitive when compared with the company’s exist-
ing racers, and while MV would eventually go on to producehttp://www.MotorcycleClassics.com 17
Carburetion on the 300B was via twin 20mm Dell’Ortos. The
vertical distributor was driven off a jackshaft on the crankshaft.