Kawi2strokes.com Forum

Jørgen Lund has kindly provided an article for posting to the Resource site. Here is the link: http://3cyl.com/mraxl/performance/perftech.htm

For future reference it is under How-To> Performance Enhancements

A big THANK YOU!!! for sharing the time, effort, and knowledge to our community.

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Answers are here: http://kawatriple.com/

Thank you Dale and Jørgen for this interesting information.

And where do we source the mentioned 2mm thick gaskets in order to lift the cylinders?

Edited: Answer to myself (thanks Looney from an earlier thread) - http://coppergaskets.us/

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"Only cheat the cheaters, boy - you can't cheat an honest man!" Mordecai Jones - The Flim Flam Man.

I've seen "blowdown" mentioned a lot lately. Can we get a definition here? I have an idea about it but it's just an idea.

From the web:

"Always measure blowdown in degrees of crankshaft rotation from the point where the first exhaust port (highest one) opens to when the first transfer port opens. By definition, that is blowdown."

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If it surges, that's normal, upshift.

Some people get time/area mixed up with blowdown. Blowdown is as Jim described, time/area is taking into account the size of the port and open duration, on order to try and equalize the flow through the motor.

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

Thanks Jim and Moo for the clarification.

Blow-down is a process inside the engine between exhaust process start and transfer process start. Blow-down varies depending on engine speed and load.
Duration, time-area etc. are just mathematical (inadequate) ways to describe blow-down.

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2x 69" H1

argo1974

Precisely argo,

Geometry is one thing.

Actual gas flow is quite different.

cliff

As with anything in engines, there has to be some kind of mathematical baseline, that's blow down numbers. Just like lobe centers on 4 strokes. It takes a super computer to show actual flow figures. Most of us don't have one. But there is decades of measuring blow down with port heights. They are totally valid.

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