https://www.youtube.com/watch?v=yK1g6wyZ4Rw

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I came across this youtube channel of a guy who hits the track on his ninjette and does all kinds of crazy experiments with it.

Last episode with the ninjette he removed the balancer just to see how the bike performed on track. This episode he explains valve timing and overlap.

His end goal is to try and get to 180km/hr on the straight of his home track. I watch with auto translated to english subtitles and with his visuals I can understand everything even with some translation errors.

He actually reads and reacts to my comments as well, lets show this guy some love from the US ninjette community!

Good find!

To reach 180kph, he'll need to get about 45bhp out of engine.
Certainly possible with big-bore high-compression pistons.
Retard intake-cam. More duration and overlap. Higher lobe-centres.
Still need to do something about restrictive intake-ports.

Must be nice to have dyno right at track so you can go out to test right after changing settings.
Having programmable EFI system makes it so, so much easier.

I knew you would love this video Danno lol

Such awesome tools! Actually measuring cam specs, that's real tuning!!!

I'm not sure which model GPX-250R he's referring to, could it be our '88-07 pregen? Those cam-specs can't possibly match new-gen's. Early '88-93 had massive cam, something like 290-degree duration! That's partly how it was able to make max-power around 12500 rpms with very little torque-drop in upper-rpms. Caused lazy low-end though. The '94-07 pre-gens had tamed-down cams and had much better more civilised low-end without massive upper-RPM hit (like 2-strokes). EDIT: Ah, he's referring to aftermarket Beet cams. yes, those may match early pre-gens. Maybe I should get my hands on set... hmm...

Didn't think removing balancer would do such. It does save about 4bhp on 250bhp Porsche 951 engine. But removing balancer caused issues (aside from vibration), such as cracking oil-pickup tubes going to oil-pump, leaking oil-pan gasket etc. 944-spec racing rules forbid removing balancer-shaft belt due to headaches it caused and goes against goal of cheap clean fun. That and no one wants to be following you when you dump entire 8-quarts of oil on track! :eek:

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