i know what you are going to say, BIG BORE KITS = TRUE HORSE POWER. mickey dont get me wrong, i still would like to have one.

the big ? is, if you take a sport quad of any brand and look at its HP rateing and compare it to ours it doesnt add up. i know you cant compair a sport quad to a utilty quad, but we have a V-TWIN it should make more. 400 ex- 650 or 700p, we have 300 cc more. are you telling me that it takes 250 or 300 cc to gain that little power? are you saying a 250cc is wright on the heals of a 400cc, i dont think so. i know that we are heaver than the EX, RAPTORS, DS'S and so on.

what im getting at is, theirs power in that V-TWIN that we own. why cant anybody find it with out a total rebuild. ( mickey no hard fealings, i still want one but i have questions)

back in the late 60'S ( i wish i was old enough to drive then) the usa went through a BIG CUBIC INCH WARS ( BB CHEVY'S, FORD'S AND THE BIG HEMI). where the lamborgine's, porsha and ferries were building small CI motors that would out run any of our stuff, stock for stock.

___________________
02 650P
NYROC MUFFLER
SUPER SNORKLE
155F/157.5R JETS
NEEDLES SHIMMED .033
3 1/4 TURNS ON THE PILOTS
DYNATEK CDI, I KICK BACK SO FAR
EPI BLACK
700P DRIVE SPRING
WARN 2000
PLOW
BIGHORNS

 

A Horsepower= 550 ft-lb/sec.

What that means is horspower depends on the torque and the RPM at which the torque is applied.

To get more horspower, you need more torque or more RPM or both.

You are looking at sport quads that do not have to put out such a wide power band like the Prairie. That wide power band is provided by the cam profile. Kawi desinged it that way on purpose so that when we nail the gas we get power at whatever RPM. If you do that on a bullet bike you will find no power down low. My car is actually like that. It won't make power at low RPM's. It starts pulling at 3000 and really goes at 5000. My car engine puts out more power per CC than anyone's truck, including the new hemi, and including that new 10 cylinder sport truck dodge makes. But my engine doesn't have a favorable powerband for a truck.

The best way to get more torque is through displacement. Mickey knows this better than all of us. More torque at the same RPM's means more horses.

A well known trick to get more horspower is by changing the cam profiles to make the engine make more torque at higher RPM's. This raises the horsepower even though the engine isn't any bigger. Often adding a cam that raises horsepower will also cause reduced low rpm torque, bad idle, increased exhaust emissions. I think mickey has worked to find a cam profile that will give us as much as possible without killing our low end power.

Another well known trick is to increase the compression ratio. This basically raises volumetric efficiency, meaning the engine sucks more air each intake stroke. Mickey uses this fact to make up for lost low RPM power caused by the wilder cam. He allows you to have your cake and eat it too if you raise the compression ratio at the same time that you use his cams. Stiffer springs also factor into this if they are needed for higher lifts and RPMs

Some of the other things like head work are to help raise volumetric efficiency (more air in). The effects are obvious. It is just like swapping the stock snorkle for the DG one. More air - more go go. This is more important for high revving motors. It is also important if you expect more flow from compresion or cams.

All of these things interrelate. The most expensive could be the displacement, but it is the easiest thing to get right. The most complicated is the cam, since you can't just simply buy a "bigger cam". I am sure mickey knows better than all of us which cam will work favorably and which will cause a low RPM bog.

You are right that the 650 and 700 doesn't really put out that much compared to some other engines.

You can improve it without adding displacement. You would need more compression, head work, and if you use the right pistons you could use mickey's cams. If the low RPM power is reduced by anything you did, you could fix it with spring/weights that raised the stall up a bit.

 

nyroc - what head work would do ? polish the runners ,port match mabe raise the ports ?

 

NYROC
well put! i understand what you said.

now the next big question is, what did kawasaki do to retard it severely? ahh the cdi.
im reading my copy of atv action mag. that was printed back in november 2002. the kawi reps hooked them up with a tricked out 650p. they installed a pro curcuit exhaust, they opened up the air box ( it looks like 28- 5/8" holes and 8- 3/8") and the world renouned original black box (cdi). why cant we get that cdi as aftermarket componnet? this is a quote from the mag., (the kawi. guys warned us that the hot iginition would make a 650p wheelie so easily a few highly experienced testers were caught totally by suprise). they didnt tell them that the original cdi was in it till after the testing. now granted they removed some weight from this machine, the front drive, racks and some plastic. they had special 25" paddle tires made, they did all there testing in the dunes.

would i get the same results with the dynatek?

why hasnt anybody matched the stock (1st original) cdi?

no im not removing my front diff. but what if you could get the same results!

mickey do you offer a high compresion piston & cams for the stock 650p? how much?
______________
02 650p
nyroc muffler
super snorkle
155f/157.5r jets
needles shimmed .033
3 1/4 turns on pilots
dynatek cdi, 1 kick back so far
epi black
700p drive spring
warn 2000lb
plow
bighorns

 

I don't believe a big bore kit is required to make big power. I believe its the internal mods that work together than make the power. An extra 100cc on a 700cc motor will not make your quad into a rocket ship. If a big bore kit ONLY raised the CC's you wouldn't get big power, you would hardly even notice a difference.

I think what Kawi did to that first quad is their little secret, it probably wasn't the most reliable beast either. We can make big wicked power but the general public does not want the added maintenance.

There are motor secrets that Kawi will only know because they designed it. They pumped in many many R&D dollars into that motor, they probably made a couple extreme motors just to test it out. So its totally possible, very possible. The question is do you want the problems and headache that kind of power gives you? The answer for 99% of Kawasaki owners is no.

 

There is a guy in Seattle that rigged a dyno so they could get a true HP reading on the Vforce and the only way to do that is at the crank, according to several people that I have talk to you cannot dyno a belt drive machine at the rear wheels and get a true reading. Mickey Dunlaps 785 big bore kit produced 78.9 horsepower at the crank, that is almost double a stock bike,NYROC thread is right on the money, it is a combination of everything, I did not notice much of a difference with a after market CDI other than the bike runs a lot cooler, thats worth the price alone, personal opinion of course. with nitrous shot an extra 15 horsepower for a total of 90 hp for at least 8 seconds any way.

 

I wonder if this thought has any value...

It seems to me that a good way to measure "effective horsepower" (not at the crank, not at the wheels, but the actual energy put into the dirt) of a machine is to weigh the machine, weigh the rider, and then go out on a flat surface and peg the throttle while measuring acceleration. Your gps (with WAAS ) might be a satisfactory way to do it. If people did those tests and posted the results they would be golden... not only as a proxy for horsepower but in and of themselves they'd have a great deal of value.

That acceleration characteristic is what you're trying to understand anyway when seeking the elusive torque/hp curve and you don't need a dyno to get it... just a GPS, a PC, and some math skills.

Has anyone done it?

 

Another thought, also, is that you lose quite a bit of horsepower through the belt drive system. The gear driven quads have an advantage there.

 

flashturbo
im not saying i know everything, if i did i wouldnt be asking questions. but the only problem i see with your testing (quad,rider weight + speed=horse power) is someone streching the truth, not everyone. ive seen people answer a question one day and a week later they ask it.

bbertram
i would like to have that wicked power. would i use it to its full potential everytime i rode it, NO. but knowing it was their would be great. you can make reliable power with out loosing driveabilty or dependability. ( those are my 2 big words for the day) ive seen street leagle cars running on pump gas with high compression producing 600 hp and plus. i know they dont drive it everyday or to the super market. but if these people can do it with a 3000lb car, why cant we do it to our quads?

__________________
02 650p
nyroc muffler
super snorkle
155f/157.5r jets
needles shimmed .033
3 1/4 turns on the pilots
dynatek cdi, 1 kick back so far
epi black
700p drive spring
warn 2000lb
plow
bighorn's

 

Big time power + aggressive riding in mud and water = fun but it also equals headache, you bust axles, you strip stuff, the motor needs more rebuilds. Everyone says they want big power but once you have to replace an axle shaft every month it gets a little old. If your running tires with big grips and your roasting the tires at 40 mph in the mud and they catch on a big rock or root kiss alot of stuff goodbye.

Big power is not meant for quads that go offroad, they are meant for people who basically drag or are very rich and can fix stuff every month. They make up 1% of the kawi owners.

What I'm saying it for what the Praire does the motor may stay reliable but for maybe 1 year but you will bust alot of other stuff in that year.