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Discussion Starter #1
There is no explicit answer other than efficiency...

When Kohei Yamada, designer of Kawasaki’s original Ninja 900 of 1984, planned this supercharged ogre-bike that started as a skunkworks project, he asked the aftermarket for a blower that could do everything he wanted it to do and work well without a bulky intercooler (no room!).

“No way,” came the reply. Compressing air makes it hot, and if that heat is not removed, it pushes combustion toward knock or detonation. So Yamada went to Kawasaki’s own Gas Turbine & Machinery Co., which designs and manufactures jet engines. They designed a fast-spinning centrifugal compressor whose high efficiency would heat the airflow least.

That compressor’s 2.7-inch impeller is the heart of this motorcycle and has the beauty of natural law. Manufactured from a forging, it spins at up to 140,000 rpm. Air is flung outward from its six vanes at up to 1,500 feet per second, and then this velocity energy becomes pressure peaking at 38.4 psi in the blower’s scroll housing. This pressure is ducted upward into the “highly rigid” aluminum airbox, containing the engine’s four steeply downdraft 50mm Mikuni intake throttle bodies. The airbox has to be rigid for the same reason 747 fuselages are: They are pressurized.
Which then contributes to the lower 8.5:1 compression ratio, it takes into account what happens upstream in the airbox...

Because so much compression takes place in the supercharger, engine compression ratio must be reduced to 8.5:1. The cast pistons (as in two-strokes and in gas turbines, materials with highest hot strength cannot be forged, only cast) have flat, featureless tops and no squish: In supercharged engines there is intense charge motion from their higher intake velocity, and the open combustion chamber preserves flame-accelerating turbulence all the way to TDC. Each piston’s heavy thermal load is handled from below by two oil jets. For reduced friction, there are two compression rings and an oil scraper. The special connecting rods have larger big-end bearings and larger (than ZX-10R) rod cap bolts.
So yea no intercooling but Kawasaki has mitigated the heat through small efficient applications throughout the powertrain. Sounds like a bunch of brilliance if you ask me...
 

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Thanks Bazza

This is what I have been saying from day one. They engineered this supercharged system,
differently from all previous systems. It is genius engineering, and design.

The two oil jets squirting oil from below is insane.
The high efficiency centrifugal compressor, reduces heat.
 

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With all due respect, you guys need to stop trying to tell us what's up and stop drinking whatever Kool Aid Kawi is pouring.

Some of us, including me, have been working with forced induction for 20+ years. I understand the principles. I don't give a F what this "author" of yours says. He has no idea what the F he talking about, as proven by his erroneous statement on cast pistons.
His assertion of cast pistons proves he has no clue what the F he is talking about.

The bottom line is the H2 would have been better off with some sort of intercooling. AIR/AIR, Air/Water, Meth Injection, etc.
I don't need Kawi to spoon feed me. I am experienced in this department and I can think for myself.

Furthermore, the price is so ridiculous, and the power for the H2 is so close to what can be done naturally aspirated, the H2 street is a fucking joke.....especially at 525lbs.
 

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I got to wade in here,and agree with 1Krider
even with a compressor map optimised for this particular motor , compressing air makes heat
try putting your finger over a handpump holding it tight and pumping, you can feel the heat burn your finger
No matter how well they have done, effiancy would improve with a form of intercooling, watch out for a power up kit in the future, if not from Kawasaki then aftermarket

be real easy to put a water/air intercooler on that bike , not much advantage on the 200hp version, it will only be pushing 5-7 psi and not creating enough heat to justify the expense , but the R at i guess around 12-14 psi will be a noticable hp iimprovement for little extra weight gain
 

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Discussion Starter #6
@OzBooster, appreciate you chiming in with relevant information instead of crowing that I KNOW BETTER!!!!

What you say makes sense yes, and 1K could make sense if he was able to read...

When Kohei Yamada, designer of Kawasaki’s original Ninja 900 of 1984, planned this supercharged ogre-bike that started as a skunkworks project, he asked the aftermarket for a blower that could do everything he wanted it to do and work well without a bulky intercooler (NO ROOM!).
It was a requirement for the bike to operate WITHOUT an intercooler. This is not a conversation about what they SHOULD of done, but what they DID do within their set parameters. At that point packaging issues would be restrictive and we would of been looking at a bike with the geometry of a 14, which again was not the point. Compact was the game...
 
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Discussion Starter #7
With all due respect, you guys need to stop trying to tell us what's up and stop drinking whatever Kool Aid Kawi is pouring.

Some of us, including me, have been working with forced induction for 20+ years. I understand the principles. I don't give a F what this "author" of yours says. He has no idea what the F he talking about, as proven by his erroneous statement on cast pistons.
His assertion of cast pistons proves he has no clue what the F he is talking about.

The bottom line is the H2 would have been better off with some sort of intercooling. AIR/AIR, Air/Water, Meth Injection, etc.
I don't need Kawi to spoon feed me. I am experienced in this department and I can think for myself.

Furthermore, the price is so ridiculous, and the power for the H2 is so close to what can be done naturally aspirated, the H2 street is a fucking joke.....especially at 525lbs.
So why are you still here? I mean we all get that you think the bike is a joke, which makes me think you're a joke because you continue to waste time on something you don't view as worthwhile. Which is funny because you're a large proponent of worth are you not? If you're not going to spend your dollars why spend your time, when your time could be spent accumulating dollars for more 2006 Gixxers?

So either you're just trolling or you view your time as throwaway and available to spend on superfluous discussions on internet forums about products you don't want. The only logical conclusion from that is that you have nothing better to do, which makes you the fucking punchline...
 

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OZ-
Nice to hear from someone else who is experienced with forced induction, and not just spewing BS while acting like a total Kawi Fan Boi.


This stupid thread is just a weak attempt to discredit my original thread.

http://www.ninjah2.org/forum/engine/2289-h2r-has-no-intercooling-between-supercharger-intake-valves-weird.html


If you can make a valid point based on YOUR extensive experience with forced induction, feel free to respond in the original thread instead of starting your own little thread to simply regurgitate what some other clueless author wrote.


@OzBooster, appreciate you chiming in with relevant information instead of crowing that I KNOW BETTER!!!!

What you say makes sense yes, and 1K could make sense if he was able to read...
I actually have 20 years of FI experience. I don't need to rely on articles like you do to get my info. You had to READ someone else's article to try to understand what I was talking about in my thread, and then you had to adopt someone else's opinion as your own because you don't have a clue.

OZ just repeated the point I made originally.
You thank him, but then try to bust my balls for posting the SAME thing? Your trolling is painfully obvious.

Only a pu$$y runs his mouth while hiding behind a computer.
Keep proving to everyone what you are.

If you read my posts you'd know I have a ZX10 ABS and I'm usually at NJMP, Pocono, Atco, and Englishtown.
Let me know if you ever want to discuss this in person.
 

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With all due respect, you guys need to stop trying to tell us what's up and stop drinking whatever Kool Aid Kawi is pouring.

Some of us, including me, have been working with forced induction for 20+ years. I understand the principles. I don't give a F what this "author" of yours says. He has no idea what the F he talking about, as proven by his erroneous statement on cast pistons.
His assertion of cast pistons proves he has no clue what the F he is talking about.

Your assertion that you know much more than Kawasaki engineers makes you look foolish.

Hypereutectic cast pistons will retain their dimensions when exposed to higher temperatures much better than forged pistons. Forged pistons are better able to deal with high shock loadings than cast but undergo greater dimensional deviations where high temps occur.

So.... Kaw chose their design to deal with high combustion chamber temps.

And yes, I too have many years of building, adapting and writing fueling maps for turbo applications.
 

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With all due respect, you guys need to stop trying to tell us what's up and stop drinking whatever Kool Aid Kawi is pouring.

Some of us, including me, have been working with forced induction for 20+ years. I understand the principles. I don't give a F what this "author" of yours says. He has no idea what the F he talking about, as proven by his erroneous statement on cast pistons.
His assertion of cast pistons proves he has no clue what the F he is talking about.

Your assertion that you know much more than Kawasaki engineers makes you look foolish.

Hypereutectic cast pistons will retain their dimensions when exposed to higher temperatures much better than forged pistons. Forged pistons are better able to deal with high shock loadings than cast but undergo greater dimensional deviations where high temps occur.

So.... Kaw chose their design to deal with high combustion chamber temps.

And yes, I too have many years of building, adapting and writing fueling maps for turbo applications.
I think it might be time to get a petition going to ban 1krider :D
 

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Already gone. Now back on topic ...
 

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"Because so much compression takes place in the supercharger, engine compression ratio must be reduced to 8.5:1. The cast pistons (as in two-strokes and in gas turbines, materials with highest hot strength cannot be forged, only cast) have flat, featureless tops and no squish: In supercharged engines there is intense charge motion from their higher intake velocity, and the open combustion chamber preserves flame-accelerating turbulence all the way to TDC. EACH PISTON'S THERMAL LOAD IS HANDLED FROM BELOW BY TWO OIL JETS. FOR REDUCED FRICTION, THERE ARE TWO COMPRESSION RINGS AND AN OIL SCRAPER. The special connecting rods have larger big-end bearings and larger (than ZX-10R) rod cap bolts."

Don't most motorcycle engines these days have 2 compression rings and a ring scraper? And don't all motorcycle engines have 2 oil jets below the piston that spray oil up to the cylinder walls? I must be missing something, can someone explain??
 

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This is an old thread started by someone who was long since discredited (and banned).

But yes ... two compression rings and a three-piece oil scraper is conventional and has been for decades.

Oil squirter jets are not standard practice but are by no means unheard of. Gen 1 ZX10R only had an oil squirter jet on cylinder #1 (no idea why) although the provisions were there for the other three (but the passages were plugged). By gen 3 ZX10R, all four cylinders had an oil squirter.

No doubt the extra thermal load on the H2 engine warranted having much more oil-squirter flow.
 

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"Because so much compression takes place in the supercharger, engine compression ratio must be reduced to 8.5:1. The cast pistons (as in two-strokes and in gas turbines, materials with highest hot strength cannot be forged, only cast) have flat, featureless tops and no squish: In supercharged engines there is intense charge motion from their higher intake velocity, and the open combustion chamber preserves flame-accelerating turbulence all the way to TDC. EACH PISTON'S THERMAL LOAD IS HANDLED FROM BELOW BY TWO OIL JETS. FOR REDUCED FRICTION, THERE ARE TWO COMPRESSION RINGS AND AN OIL SCRAPER. The special connecting rods have larger big-end bearings and larger (than ZX-10R) rod cap bolts."

Don't most motorcycle engines these days have 2 compression rings and a ring scraper? And don't all motorcycle engines have 2 oil jets below the piston that spray oil up to the cylinder walls? I must be missing something, can someone explain??

Interesting first post for a new member, most people ask about slip-on pipes, or preventing paint damage.
 
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