<P> As applied to motorcycles, two - stroke engines have some advantages over equivalent four - strokes: they are lighter, mechanically much simpler, and produce more power when operating at their best . But four - stroke engines are cleaner, more reliable, and deliver power over a much broader range of engine speeds . In developed countries, two - stroke road - bikes are rare, because--in addition to the reasons above--modifying them to meet contemporary emissions standards is prohibitively expensive . Almost all modern two - strokes are single - cylinder, liquid - cooled, and under 600 cc . </P> <P> In November 2006, the Dutch company E.V.A. Products BV Holland announced that its diesel - powered motorcycle, the Track T - 800CDI, achieved production status . The Track T - 800CDI uses an 800 cc three - cylinder Daimler Chrysler diesel engine . Other manufacturers, including Royal Enfield, had been producing diesel - powered bikes since at least the 1980s . Also, Intelligent Energy, a British alternative - fuel company, is developing a motorcycle powered by a detachable hydrogen - powered fuel cell, which it calls an Emissions Neutral Vehicle (ENV). According to reports, the vehicle can sustain speeds of 50 mph (80 km / h) while making virtually no noise, and can run for up to four hours without refueling . </P> <P> Most modern motorcycles have a sequential manual transmission shifted by a foot lever . Some motorcycles, and many scooters, use a continuously variable transmission . Other types of automatic transmission and semi-automatic transmission are also in use . </P> <P> Engine power can be engaged or interrupted through the clutch, typically an arrangement of plates stacked in alternating fashion, one geared on the inside to the engine and the next geared on the outside to the transmission input shaft . </P>

Where is the front brake lever on a motorcycle typically located