THE HONDA HAWK

When Honda Gets Serious About Something,

They Don't Foot Around

by Bob Braverman

Those people who are even slightly

familiar with motorcycle competition

are aware that the world s largest

motorcycle manufacturer has, in a

relatively few years, gained the envi-

able reputation of being very success-

ful at virtually everything they tried

For years, Honda had dominated GP

world competition, and likewise dom-

inated the motorcycle sales picture

through a concerted effort with only

one goal in mind, and that was to be

the most successful company at

whatever they tried.

Looking for new fields to conquer,

last May Honda made the decision to

turn their attentions to garnering the

all time land speed record for motor-

cycles, and they proceeded in typical

Honda fashion They looked around

to get the best talent available. From

all indications, the road to success

looks fairly smooth and unobstructed

Early in the game, it was decided

that a pair of 750 four cylinder en-

gines like those found in the standard

motorcycle would be pressed into

service, mounted in a very conven-

tional manner. Since time was a major

consideration, it became mandatory

that as many standard parts as possi-

ble be utilized. Development and con-

struction of special racing components

is a very costly and time-consuming

situation. The fact that Honda has

achieved the results they have with

the relatively stock pieces is rather

incredible, and a real tribute to their

basic engineering.

Honda felt there were two basic

approaches to getting a lot of horse-

power One was to build exotic en-

gines and turn them considerably

higher. The other was to supercharge.

Supercharging won out for several

reasons. On the surface, it's consid-

erably easier to use fairly standard

engines and introduce a blower capa-

ble of producing an adequate boost

in atmospheric pressure. After build-

ing an engine cradle from hefty alu-

minum plate, two crankshafts were

coupled together using fairly large

sprockets and a fairly long section of

special chain. Early in the game, it

was decided that rather than saw the

transmission off the front engine, they

would use both transmissions and

both clutches. If everything goes well,

there is no problem in doing this. This

writer, though, in having built a

number of dual engine projects, has

serious reservations about the wisdom

of attempting to follow this line of

thinking. In any event, all of the test-

ing to date has produced nary a prob-

lem, so if all goes according to plan

the two clutches and gear boxes may

work without a hitch.

The engines utilize mostly stock

A mock-up of the control

system complete with gear

position lights is in the lower

left corner. The scale weighs

the amount of fuel the engines

burn in a given period of time.

The degree of instrumentation

and sophistication is quite

impressive. Just about

anything you might want to

know about either engine

while running on a dyno can

easily be checked here.

Believe it or not, underneath

the ducting, wires, cables and

other paraphernalia, there

reside two rather standard

Honda 750 four-cylinder

engines.

The turbo charger itself is a standard AiResearch unit, and

interestingly enough only one unit is used to supply air to

both engines.

components. Early preliminary testing

consisted of using the AiResearch

T-04 turbosupercharger, but it was

discovered that after introducing more

than 1 5 pounds of boost, the standard

connecting rods were no longer ade-

quate to the demand placed on them

In doing a little further experimenting,

the people in the engine department

discovered that by smoothing up the

rods, shot peening and reheat treating

them, the rod problem vanished over-

night. Standard pistons and piston

rings are used, along with the stand-

ard cylinder and cylinder head. Even

the standard valves and valve springs

are used. Material was removed from

the combustion chamber in an effort

to reduce the compression, since a

fairly large blower boost is used. High

compression and large amounts of

boost introduce detonation, not to

mention fantastic bearing loads and

heat.

The standard carburetors were dis-

carded in favor of a specially built

Hilborn fuel injection system designed

specifically for this project. Two four

cylinder injection units are used to

deliver the straight alcohol to each

engine.

Another interesting thing was dis-

covered when Honda embarked on

mis engine development program.

The turbosupercharger works far bet-

ter on a multi-cylinder engine than it

would on the same size engine using

only one or two cylinders. Since the

blower is delivering pressure to eight

cylinders instead of just a couple, the

Honda and AiResearch technicians

feel the chance of blower problems

is greatly minimized. The exhaust

gases are the driving force that turns

the supercharger, so blower drive

problems are non-existent. The hot

exhaust rushes through the specially

built stainless steel ducting to the...