The Rise and Fall of the Two Stroke Quad

There's nothing quite like the scream of a two strokeexhaust emission all happen on each cycle (or
engine and the smell of burning engine oil is alwaysrevolution) of the engine. Four strokes in comparison
right there with that scream. In the world ofuse a camshaft and a series of valves to separate all
motorsports its sound is unmistakable. Dirt bikesthe phases of energy production. These additional
would see the two stroke engine utilized on earlycomponents add overall weight to the four stroke
models because of the smaller size. Snowmobilesengine. The two stroke however must burn oil during
would also follow suit because of the light weight. Itits ignition phase. This accounts for the blue or grey
was only a matter of time before the ATV wouldsmoke which emulates from every two stroke
make use of the technology to improve response,exhaust port. Two stroke engines require oil to be
increase speed, and reduce weight. The first twoinjected simultaneously with the fuel or pre-mixed in
stroke quad made it to market back in 1985. Thethe fuel tank. Two strokes also burn more fuel
Suzuki Motor Corporation would design and releaseversus the four stroke powerplants. Citing emissions,
the Quad Racer, a two stroke racing quad with anoise pollution, and higher fuel usage, the two stroke
246cc powerhouse. Although two stroke enginesengine has all but been eliminated from automotive
were appearing on earlier ATC's from the big fourand street motorcycle market, but the lightweight
manufacturers (Honda, Kawasaki, Suzuki, andsimplicity and sheer horsepower per cubic centimeter
Yamaha), this quad in particular would set off aof these engines allowed them to flourish in the
revolution of racing and sport riding. The ATVoffroad market.
brought more stability to the table with four wheelsIn their heyday, quad manufacturers flooded the
versus the three wheeled ATC's. Engine size andmarket with their own two stroke engines. Beside
power was utilized far better on quads when ridersthe big four, Honda, Kawasaki, Suzuki, and Yamaha,
became more apt to keeping their wheels beneathother big players like Polaris as well as a variety of
them. The ATC was considered unstable and itssmall scale Chinese manufacturers have capitalized on
production would eventually be outlawed, but thetwo stroke power for their quad ATVs. But new,
two stroke quad would flourish in the coming yearslightweight, and more efficient four strokes would
with all the major manufacturers contributing theireventually become the accepted powerplant for the
own version.majority of production quads. The two stroke has
The two stroke engine was first invented back inbeen completely dropped from the lineup of most
1878 but the first patented two stroke motor, amanufacturers in favor of reasonably quiet, fuel
v-twin, didn't come along until 1904. The two strokeefficient, technologically advanced four strokes. Sport
design has certain advantages and disadvantagesquad riding and organized racing have also, for the
when compared to a four stroke engine. One strokemost part become four stroke events. As quickly as
equals one cycle, therefore a two stroke enginethe two stroke engine entered the atv industry, it
completes its energy production using half the cycleshas, for the most part, fallen by the wayside even
of a four stroker. This is because two stroke engineswith new advances in emission technology, including
have no valves. The fuel intake, fuel ignition, andreductions in odor as well as smoke.