This was the production race machine of choice
for anyone who was serious about winning. It
was fast, reliable, and once set up, could be
run for a complete season without trouble. It
was not the lightest machine in it's class,
but handled well, and of course to win a race
meant having to finish a race, and that is where
the fast but fragile Bultacos and other air
cooled two strokes could not always pass muster!
In fact untill the Granby tuned YAS1 appeared
in 1970, these glorious little Honda's ruled
the British short circuit scene for over 7 years!
As well as looking fabulous, with their 180
degree crank pin, sounded superb on open megaphones,
drowning out every other race bike on the track!
The close spacing of the cylinders, by utilising
a gear driven cam drive on the left hand side
(as you sit on the bike and look down), meant
little in the way of rocking couple, something
which affects larger 180 degree twins, notably
the CB450. Most of these were four valve heads,
but I was told by an ex works Honda rider, that
he actually raced a two valve version, if anyone
out there can verify that, I would be interested
So we have a vibration free engine producing
20BHP (some say 24BHP @ 13000 rpm) at 11500
rpm. Because of almost zero vibration, the engine
would run right up to a safe 13000 rpm, and
beyond, but using this amount of revs to often
would result in less reliability. The machine
was easy and forgiving to ride, although produced
no power at all until 5800 rpm, and suffered
'megaphonitis' until 8500 rpm. It was easy to
keep in it's power band, when pulling 13000
rpm in third, or fourth gear would result in
dropping to 9500 rpm on the up change, perfect!
Information kindly provided by www.honda-modernclassics.com.