god knows they really have to wring out the KLX300 to get it to hop...
oh, found this on klxzone...
Measured at the rear whell the Team Kawasaki KLX's crank out 34 horsepower. To put that figure in perspective, out of the box a KLX250 produces and uninspiring 18hp. Take a look at the devlopment that nearly doubled the KLX's power output.
• The stock piston was discarded in favour of a high compression Wiseco piston. The piston used is actually made for Honda 1100cc road bikes and requires machining to suit the Kawie.
• The 2001 thumpers are slightly down on performance compared to McFarlane's 2000 thumper because of this year's strict fuel restrictions. A higher compression piston was used in Andrew's bike because it drank hi-octane fuel.
• It has taken two to three seasons to develop a camshaft that Kevin's satisfied with.
• For durability reasons a forged steel Carillo conrod replaces the standard rod. Kavin had the conrod purposely built 2mm longer than the stock rod. As well as raising the compression slightly, the longer conrod also makes the KLX pull stronger.
• Plans are afoot to alter the combustion chamber to allow higher compression without detonation on pump fuel.
• The cylinder head on the factory four-stroke is very similar to the head on a production KLX. The port shape remains the same and the valves are stock standard. The only improvement is a clean-up with a porting tool.
• Staintune Australia and Kevin Doyle worked together to develop and exhaust system that suited the KLX. Modifications were made to the system to fit the KX subframe.
• The standard black box has a rev limiter that puts a cap on the revs at 9500rpm. A vortex ignition replaces the stock unit and has been programmed to rev to 11,900 rpm during dyno tests, the horsepower of the KLX is still climbing when it hits the 11,900 mark.
• A 37mm FCR carburettor replaces the standard carby. This modification alone makes a massive improvement to the KLX's low to mid-range performance.
• Heavier than standard Barnett clutch springs are the only non-genuine components inside the clutch.
• To enable the engine to reach maximum revs quicker a modified KX250 flywheel replaces the KLX flywheel. The KX flywheel is nearly 1.5kg lighter than the KLX equivalent.
• Kevin makes up a modified kickstart gear because standard KLX's have been known to break kickstart gears. The problem can also be solved by changing the decompression timing. According to Doyle the timeing is too far advanced which gives the bike too much compression when starting. Retarding the timing lowers the compression which reduces the strain on the kickstart gear and also makes the bike easier to start, because the engine turns over faster.
• The KLX's run Maxima 100% synthetic oil, which is replaced after each race meeting. Apart form that the engines don't receive any extra maintenace throughout the season. Last year, Andrew's thumper was pulled down a couple of times to check for wear but each time it was nailed back together without any replacement parts. The same piston and rings were used for the entire season.