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116 | AUSTRALIAN ROAD RIDER

engines with more power, but ultimately

be er fuel economy.

The complexities of supercharging

systems have come a long way thanks to

development in aeronautics, automotive

and marine applications. In fact, the

lessons learnt in marine applications are

cited by Kawasaki as a reason why the

manufacturer showed a supercharged

four-cylinder engine at the 2013 Tokyo

Motor Show: the engine that was to

become the Ninja H2. While Kawasaki

didn’t go into any detail at the time about

the engine’s future application, it clearly

points to the fact that superchargers

have a future.

Chargers are essentially pumps

that give the engine an extra push by

forcing more air into an engine. This

in turn allows smaller capacities to be

run with a supercharger or turbo and

receive an output similar to a bigger-

capacity engine.

Where the two systems deliver in

their operation is, generally, in the way

they apply their initial eff ect due to the

fact that turbos are typically operated

off exhaust gases and superchargers off

the cranksha.

Both systems are essentially air

compressors that increase air pressure or

air density to a combustion chamber. The

increased amounts of oxygen can burn

more fuel and thus make more power.

The two systems diff er where a

turbo runs post-combustion. Air

from the exhaust turns a turbine that

increases the pressure in the inlet tract.

Superchargers are operated mechanically

in a number of diff erent ways, typically

off the cranksha. Belt, gears, chains

and sha s turn the compressor which, in

turn, forces more air into the intake tract.

There are two general negatives to the

systems. With a turbo, when you twist the

thro le there is a delay as an increase in

exhaust gases is needed before pu ing

the turbo into eff ect and pressurising the

inlet tract. Revs are needed for them to

“One way for the Japanese

to beat this tariff and

produce a motorcycle with

the sort of power of a big

bike was by running a turbo”

r Drivetrains for superchargers are sometimes used

as a showpiece like this one!

ARR112_112-118_Turbo & Supercharged.indd 116ARR112_112-118_Turbo & Supercharged.indd 116 2/3/2015 9:52:55 AM2/3/2015 9:52:55 AM