Is this pretty factual, or just someone trying to think too hard?? Is there any evidence that this is true? Wow, we would have a lot of yammaha and honda guys switch over then, that would be great. I hope Polaris does something like that, so they can keep building their business. Wow that quad would be amazing though wouldn't it?? 18,000rpm?? What would that even sound like, seems like it would sound like it was about to explode underneath of you.

 

...I want one!!

 

lol think of the coolinh system needed for 18,000 RPM...lol itd be nice of they came out, but think of the cost.

 

you should watch a formula 1 race once in a while...those engines rev out close to 20, 000 RPMS, and i think there aircooled. and they scream.

 

IMHO 18,000 rpm isnt really a big deal considering most sport bikes redline at around 14-15 thousand and the wr450 and possibly the yfz redlines at 12,000 or somewhere around there. Im also scepitical(sp?) about polaris actually putting out a 450 because as must of u know they make a 440 debore kit to allow the predator to run in the 450 classes, im thinking if u want to race polaris will make this kit more available to the general public and still keep the 500 motor as stock equipment for trail riders. I also have to say that I noticed a small write up in atv action on page 10, heading "OVAL PISTON HONDA 440EXR" that states this "we might even see something as wild as an eight-valve, twin sparkplug, oval piston 440cc single. This design allows a motor to breath like a tiwn, while retaining some of the simplicity, narrowness and power characteristics of a single." so im sure this is just a rumor. [img]i/expressions/face-icon-small-smile.gif[/img]

BTW im a die hard polaris guy and I actually would like to see a predator 450 but honestly who needs the 450 motor when u can virtually have the quad mx ready off the floor with a 500 that will beat the other 450's, and if u must race in the 450 classes go out and buy a 440 kit or get the dealer to swap it on before u buy it. Cool [img]i/expressions/face-icon-small-smile.gif[/img]

Mike M

 

F1 's are definitely NOT aircooled.

And the difference between 12,000 RPM and 18,000 is immense to say the least. F1's use pneumatic valves to run that high. You're probably not going to get a mechanical cam follower to accurately actuate valves at those engine speeds. Getting oil to it and keeping it cool would be tough enough but add in the need for an intricately balanced motor the expensive parts that are strong enough to withstand such RPM is gonna be rich. Any vibration would tear the thing up.
I can see rod ratio being key in a motor that spins like that.
RPM's are what kill motors and getting one to live for very long at that kind of RPM is a feat with current technology. No wonder they costs hundreds of thousands of dollars for one. And to put one in a machine that runs in dirt?? Wow.
This is why we race, and one day it may be possible and reasonale to procure, but not yet. They aren't even there with street bikes.

 

it can be done,most high tech 4 stroke builder are capable of testing
their engine up to 20000 rpm,but they always tend to slow them down
to 10000 or so,what i try to say is that,we aren't see anything new on 4 stroke technology yet,i think the future is coming with them after
putting a lot of testing through,let' see.

 

lol..ur right, its just that they have no radiator fan

 

lol with that kinds power, youd pretty much have to be leaning over the handlebars just to keep all 4 wheels on the ground. and you could just as well go from neutral to 4th gear without it stalling. damn all this uberquad stuff is making me crazy

 

I'd suppose a fan is not needed at over 200 mph. [img]i/expressions/face-icon-small-smile.gif[/img]

A friend I worked on cars with in my early 20's now works for, I believe, Minardi as an F1 team engineer this year.