450 Honda Super Sport (CB-450 K2)
SUPER SPORTY
' 4 ’
ROADRURNER
Mr. Honda’s 450 low-piper is an engineering delight built
for the enthusiast who knows what’s happening.
THE JAPANESE HAVE long
been known for the “building
the better mousetrap” syndrome.
This has enabled them to become
the leaders in almost every field they
enter. Toyota in cars, Sony in TV,
Akai in tape recorders and Honda in
motorcycles. In this respect, what
Sony is to TV, Akai is to tape re-
corders and Toyota is to cars, the
Honda 450 Super Sport is to motor-
cycles.
Getting off to a bad start in the
original CB-450 version, Honda took
the hint—poor sales—and revamped
it completely. Everything was up-
graded—the motor, frame, suspen-
sion and gearing. The bike also went
through many design changes result-
ing in the current version which is
really groovy, almost the epitome of
fine, dynamic styling.
The most important singular fea-
ture of this superior machine is the
much acclaimed, much talked about
and much written about 444cc 4-
stroke double overhead cam twin
cylinder, ultra refined powerplant.
Aside from the double overhead cam
arrangement, the engine has plenty
of other progressive features.
Valves are of the torsion spring
type as opposed to the conventional
spring type. This system has proved
to be ideal—trouble free and highly
efficient. The only limitation here
is in adjustment. The setting screws
—the tolerances are set from the
outside—are touchy. You need one
hand on the screwdriver and one on
the wrench holding the outer nut.
Tightening the nut will sometimes
cause the inner screw adjustment to
slip and the whole magilla has to be
reset. Then too, with one hand on
the screwdriver and one manipula-
ting the wrench, what’s to hold the
feeler gauge to adjust the space tol-
erances. Many shops make this a 2-
man operation.
Another minor shortcoming is the
necessity of removing the carbs and
the tank as well as two access covers
to adjust the valves. As stated before,
however, these are minor and when
you consider the superior mechani-
cal performance of this set up, a
small price to pay.
The 450 engine puts out a strong
43 horses at 9000 rpm. Bore and
stroke is a 70 x 57.8mm. The short
stroke allows plenty of revs through
the gears. Compression ratio is 9 to
1. The intake valves are really big,
another plus factor. The intake
vales measure 1 3/8 inches and the
exhaust valves measure 1 3/16-in-
ches. Valve float is kept at a mini-
mum because of the highly efficient
torsion bar valve spring system. The
camshaft valve actuating mechanism
is driven by a long resilient drive
chain kept at constant tension with
the aid of guide rollers and by a
spring loaded tensioner adjusted
from the outside.
Main bearings of this engine total
four in number, each bearing a
caged roller held by pillow blocks
in the upper portion of the crank-
case. Four roller bearings keep vi-
brations to a minimum. Primary
drive is off a small gear from the
crankshaft rotating the gearbox main
shaft, through a large clutch gear.
The friction clutch is of the wet
multiple-disc type, housing six
powerful springs.
The carburetors on the 450 are
reputed to be the finest ever in-
vented and superior in many ways
to other carbs in general use. They
are of the constant velocity vacuum
piston type.
Here is the basic operational prin-
ciple behind these carbs. As the pis-
ton in the engine begins its intake
stroke, the intake valve opens. A
vacuum is created and a mixture of
vaporized gas is drawn into the com-
bustion chamber. At minimum throt-
tle openings air is ingested by the...