Kawi2strokes.com Forum

Ok, so, not a triple, but does fall into the category of Kawasaki two stroke, my work of the last 18 months. I have filed and received the application number for patent for this. Have almost an hour of ride time on it, few issues I'm still dealing with yet but so far i'm pretty pleased with it. Shows great promise so far. It's sequentially injected, using a Microsquirt ECU. All CAD, design, CNC machine and fabrication work you see is done by me.

_________________
1974 Kawasaki H2B 750, 1981 Yamaha XV750 Cafe, 1986 Kawasaki KDX200, 2003 Honda XR100, 2004 SDG140. 2006 Ninja 500R Turbo intercooled fuel injected.

Another pic.

_________________
1974 Kawasaki H2B 750, 1981 Yamaha XV750 Cafe, 1986 Kawasaki KDX200, 2003 Honda XR100, 2004 SDG140. 2006 Ninja 500R Turbo intercooled fuel injected.

This is pretty amazing, but please describe how you were able to make the conversion. Like what is the gas flow path, for example?

_________________
If it surges, that's normal, upshift.

The goal, or it's advantages are, high power density, high efficiency, low emissions, long life. I love two strokes but hate their shortcomings; short life, emissions, etc. So I set about to fix all those problems. I have to compare it to a four stroke as installed in 95% of the engine applications for size, the four stroke head can't compare to the two stroke we know. It seals the crankcase off through the lower piston stem with stationary oil rings, but still uses the piston to pump/ supercharge the incoming flow. This is a necessity, a Detroit Diesel two stroke uses a separate supercharger so is complex and has shorter life, not to mention the huge long piston it uses for it's design.
Modern automotive design is seeing less cylinders and boosted, this covers that area well, but is less complicated. Can use a turbocharger if needed, does not need expansion chambers. Reed intake, piston controlled transfers, poppet head exhausts.

_________________
1974 Kawasaki H2B 750, 1981 Yamaha XV750 Cafe, 1986 Kawasaki KDX200, 2003 Honda XR100, 2004 SDG140. 2006 Ninja 500R Turbo intercooled fuel injected.

Well, it sounds very interesting, but that's not enough description for me to visualize the gas flow, particularly the part about how you sealed a volume below the piston.

_________________
If it surges, that's normal, upshift.

This page from the patent application shows it all.

_________________
1974 Kawasaki H2B 750, 1981 Yamaha XV750 Cafe, 1986 Kawasaki KDX200, 2003 Honda XR100, 2004 SDG140. 2006 Ninja 500R Turbo intercooled fuel injected.

Ahhhh! Thanks, that explains it. Very well done. What HP/cc are you seeing so far? I understand you're just beginning the running of it.

_________________
If it surges, that's normal, upshift.

I really have no idea yet. It certainly has more power than the stock four stroke at lower rpms, and I haven't gone over 7400 yet. The stock motor was dead under that rpm, this one is pretty torquey and smooth, as it would be with an even firing order and twice the power strokes. It sounds sort of like a different hot four cylinder four stroke, but has some of the exhaust tailpipe pulse a two stroke has. This week I pulled the motor and advanced the exhaust timing up 12 degrees, and it really liked that. Also a huge gain over a port two stroke, it has asymmetric exhaust timing. Been advancing the spark map last few days, creeping up on that slowly.

_________________
1974 Kawasaki H2B 750, 1981 Yamaha XV750 Cafe, 1986 Kawasaki KDX200, 2003 Honda XR100, 2004 SDG140. 2006 Ninja 500R Turbo intercooled fuel injected.

Neat. I look forward to hearing more about it. I assume they'll be cheaper than the original 4-stroke was, since you're only getting half as many strokes.

_________________
If it surges, that's normal, upshift.

LOL! Great minds... I had a similar idea back in 94, but liked the basic 250 design better for my idea. Never had the time or money to explore. Very cool!

_________________
Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........