Thank you gary! I thought I was the only guy that backed up the Rappy, guess not! :-)

 

My mistake. I took another look at LRD's ad and it's 24hp at 7800 rpm. But that still doesn't alter the fact that the Raptor gains more from pipe, filter, and jets than any other quad. In stock trim it's stuffed up and constipated. It also doesn't change anything regarding maximum horsepower. As stated before, when it come to HP, there is no replacement for displacement.

 

I always thought that the banshee was the quad that gained the most from pipes. Either way no four stroke in the quad world will ever take the place of the banshee for sheer horsepower. If you want a drag bike why would you buy anything else?

 

the raptor and yfz 450 have the same top speed but the raptor proformes 9,000 rpms and the yfz 450 proforms 10,000 rpms

 

i agree with whoever said that the raptor comes cramped up. I think if they let it all hang out it prob wouldent be legal[img]i/expressions/face-icon-small-smile.gif[/img] if a raptor needs to loose 50 punds it can ddo it. I'm not a raptor specialist but i think they make a high comp kicker for it witch is getting rid of the battery. taking away about 20 pounds. But the list can go on and on forver. Im toried opf peoiple putting down raptors beacuase there old or in 01 they had a few tranny problems. Including 1 ways and wht not. Can we all just say that is a nice machine? someone also said that the rappy and the yfz are the same speed. THAT IS NOT TRUE. race any. The yfz is a quicker machine. It will get to 5th before rappys probobly in 3rd. a yfz will getr to top sopeed faster but if you wait here comes the good ole craptor sneeking by. 660 vs 450 any way you put it the 660 will have more hp. Although the yfz will have a better power to weight ratio but not by much beacuase a yfz and a rptor weight about 75 pounds more but its running a dohc 660. You dont need a math matition to find out if 75 pounds is enough of a change for 210 CC. A raptor is to a racer. the tihng was practicly made for gncc which is one of the most known atv races out there. That all i got..


Jbomb

 

actually its sohc

 

Just use the PLANK formula to figure out Indicated horsepower. HP=PLANK/33000
P-pressure 14.7Xcomression ratio
L-length of stroke in feet
A-area of cylinder
N-number of power strokes per minute. Take RPM and divide by 2 for a 4 stroke
K- number of cylinders

Raptor 135.24x0.276x12.19x3000x1/33000= 41.4HP 9.2:1 compression @6000RPM
161.7x0.276x12.19x3000x1/33000=49.5HP 11:1 compression

450 161.7x0.203x10.98x3000x1/33000 =38HP

So with the same compression ratio the 660 has 11.5 more HP
This is why there is no replacedment for diplacement


My 2 cents

 

wow thats a interesting formula hughjazz. I would have to agree on the raptor. Most people dont ride mx and mod for mod the raptor will gain the most. I personally feel like im on a kids quad will riding the 450. But everyone has their opinion, i would think that people would understand the phrase "no replacement for displacement". A larger engine will always produce more power if their compariable motors such as compression, cams and carbs.

 

haha you cought me trying to be smart when im really stpud haha

 

A 350 lb YFZ with 50 HP is 7 lb/HP. A 425 lb Raptor needs 60 HP to have the same 7 lb/HP. I wouldn't be afraid to wager that a good MX Raptor doesn't weigh a full 75 lbs more than a YFZ, both wet. The YFZ is easier to ride fast but will it really be faster than a high strung 727 MX Raptor?