GP Customs inc. Tech
			Predicting Power BHP=PLAN/33000 P=Effective pressure L=Piston stroke in feet A=Area of piston in square inches N=Power strokes per minute
	I)Crank Train: So what exactly are we talking                           about when I say Crank train?                  *Well its a combination of piston,piston speed                      as well as ring width,crank case volume,                      bearing surfaces etc...          Note: Think of it as a train with the tractor                      being the crank itself diving the rods                      pistons rings all depending upon each                      component for optimum performance.                      Each item effects the performance as a                      whole. Everything in motion is part of the                      train. Everything....          A)Pistons and rings:                  *Most pistons manufactured by the japanese                    manufactures have a higher silicone content                    than some aftermarket manufacturers. And                    silicone content is the name of the game                    when avoiding melting holes at higher                    Temps. For that reason I use off the shelf                    pistons unless ring width and flutter                    becomes an issue....                  *Ring width and flutter affect piston speed                    and sealing along the cylinder bore. Example: Standard rings will begin to flutter around                  60,000ft/sec2  in most two stroke street bikes                  or 7000RPM. So why use them? well they                   provide longevity and sealing far superior                   to the narrow racing ring which remains                   stable towards 10,000RPM. There are even                   kit rings that remain stable even higher in                   the RPM range. But what you do lose is the                   low RPM seal and durability.                  So why use them?,...They perform along with                  the crank @ Crank train allowing for higher                  sustained power in the upper revs. But you                                ride a modern GP machine so its been                                          designed far beyond the days of RD350s.                                              * CIRCLIPS*                  Never install circlips in the 9 or 3 oclock                   positions! Remember how fast the piston                  and ring are traveling? They will spring out                  and catch an exhaust port,...or the wrist                  pin will move out into a transfer port!
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