Case+ gearbox
The H2EX (as in ‘Extended’) billetengine features a six speed gearbox which originates from Kawasaki’s famous GPZ900R. Gearboxes with this layout can also be found inside todays ZX12, proving strenght of the original design. It shifts cleanly and has proven to be able to withstand both the rigours of dragracing as well as high speed motorwaycruising or roadracing.

3D CAD
It took four years of engineering to get the H2EX-engine to what it is today. Major challenge was it to fit this enginecase within confinements of the stock H2-frame. The oversized GPZ-gearbox is almost as long as stock H2 box + kickstart assembly. On the H2EX-engine the kickstartershaft has therefore been moved sideways, and now sits inbetween the gearbox and clutchassembly.

Inputshaft
An extended inputshaft is required to allow primairy drive to be taken from the end of the H2-crank. Actual length of the inputshaft is determined by distance between primairy drive and frontsprocket location. Stock GPZ-gears are fitted onto this new shaft.

Clutchcover
The clutchcover has become quite a bit bigger than stock since GPZ clutchbasket is a much larger than the stock H2-item. The cover houses stock H2 drivesystems for oilpump and revcounter.

Enginecase
Enginecases are milled on five axis machines which makes certain allignment of bores is perfect. Better quality material and increased wallthickness in critical areas has improved ridgidity decisively over stock enginecase. The H2EX-case offers better support to the crank and gearboxshafts. This reduces internal friction, increases output and prolongs life of bearings and gears.