to all you performance nuts

I was thinking about how Yamaha, Honda. Etc. all have some kind of street bike that is around 600cc. I have heard of people making frame fabrications to squeeze a street bike motor into a quad frame. My question to you to anyone. Why not just change the gear ratio in the trans of the quads to reflect the ratios in the street bikes?

 

Mu understanding is that the Raptor engine was, in fact, taken from a Yamaha street bike that was sold outside of the U.S.

 

yeah I have heard that also, but my question is can you change the gear ratio to make the top speed and performance like in a street bike.

 

The problem with that is
street bikes are lighter than a Raptor
A 600cc 4 cyl street bike makes it's power on the top end, it doesn't need the torque that a quad does
a 4 cyl street bike revs real high so gear ratios reflect that.
A street bike in a quad makes a good dragster but not much else.

 

The motor from the Raptor was originally from a Yamaha Bike called the XTC and another name as well... cant remember that name- these bikes are very good Dual purpose bikes sold in Europe and Japan.

 

I thought about this one a lot. Why does a stock Raptor at 660cc make 35 hp, yet a Yamaha R6 (at 600cc) makes about 120 hp? Like Moose points out, the torque isn't there, but I would think you could take one of these motors, and mod them so they are putting out maybe 90 hp, with respectable torque numbers, plus maybe changes to your gear ratios. Definately something that would launch your quad around the trail. I think maybe the manufacturers are silent partners in many of the aftermarket companies. Who knows. I had ridden a friend of mines R6 prior to getting my raptor. That thing was insane. I really felt like I was on a rocket. I really expected a similar exhiliration when I hopped on the Raptor, but it's not anywhere close to the same feeling. I have piped & jetted my Raptor, and it really woke it up, but still not what I expect from 660cc's. Now I'm looking at getting the 686 or 727 trinity motor built, but the thought of putting more money into it is hard to swallow. I don't see how manufacturers could get sued for selling a fast quad. I mean, something that truly is 100 hp from the factory. These manufacturers aren't getting sued for 16 year olds on 900's that are eating pavement everyday. Don't see that they could get sued for making a decent race quad. One of them needs to break the mold pretty soon, I'm just wondering who it will be. Seems like after the Raptor came out, everyone is concentrating on the 400cc class quads, no big high performance open class quads yet. There's the predator, but I'd rather eat my own sh^t before I bought a polaris. Until then, we're all stuck paying 12-15k to get what we want. Kinda sucks, because that's a lot of frickin money for a toy. When I'm done with the Trinity engine, I will have more in mods than I paid for the quad. 8k in mods is frickin nuts...but I need the power.

Anyway, I got off topic a little. You know what would be a sweet machine would be if Kawasaki did some mods, and put that 650 v-twin into a race quad. Now that thing would rule the open class quad market.

 

I brought and old post back up see"This is where the Raptor Power Plant was Born" Thread.[img]i/expressions/face-icon-small-smile.gif[/img]

 

A 600(4 cylinder) with (16 valves) and(4 carburtors) is going to flow a hell of alot more air than a 660 single. Haveing muliple cylinders is a MUCH more efficient way of flowing air(=POWER) thru a motor of equal size. You can only have so much piston-speed, so 4 small pistons reving at 12,000 RPM is going to flow more air than 1 big piston revving 10,000 RPM.


Biggerisbetter.