Lots of people do it.........

 

My god, can u say over analyizing this subject? Put it this way. The Raptor engine is way old. Old design. Didnt it come from some old 660 dirtibke? I believe it did. This engine was never ment to be put into a small mx bike to win championships. Yamaha put this engine in the Raptor to sound powerful. 660cc's sounds much better than 450cc in the uneducated persons mind. But obviously we all know better than this. The 450 engine on the other hand, was made to be put in small mx bikes to win championships, so therefore, more money was put into the designing of this motor. Its new technology, where as the 660 is NOT. You make it sound to be that the 450 is a new engine. It is every much different than that! The 450 was designed BY YAMAHA for THEIR products. The 660 was NOT desinged by YAMAHA. They just used it for a "big bore" quad.

So what have we learned? 450cc's can make more than 660cc's, period. Money buys horsepower. Yamaha put money into the 450, so it has the power.

Now can u just let this go CaptBags?

-Nick

 

im with big scary i think a lot of people do too at least on this sight

 

I understand the points being made. I'm pretty green to performance mods and, roughly know engine basics. I just wanted to get a better under standing of how the 450 made its power and, why it made the same as the 660 and, for what reasons..

Thanks for the Edjucation!

I appreciate your patience and, didn't mean to over analyze. I just couldn't say everything i wanted to know or, meant to ask at once because i kept thinking of more stuff!

 

I was just teasin anyways.

Even Enstien asked questions..

-Nick

 

From what i can tell your question was answered 3 times and u kept asking it again, but lets go over the facts.
YFZ bore/ stroke some room to increase
Rappy bore/stroke lots of room to increase

YFZ cam - can't improve much on
Raptor - Plenty of room to inprove on

YFZ Valve train - good setup
Rappy valve train - in the pooper

Rappy compression - 9.blahblah
YFZ compression - 11.blahblah

Rappy exhaust - sucks
YFZ exhaust - sucks

Intakes - donno (both suck?)

Rappy tranny - good lord
YFZ tranny - hope to god its good


from what I can see the YFZ, from the factory, comes with alot more performance parts than the rappy does. You cannot compare horsepower to cc's because its not a matter of cc's its a matter of being able to combust the most fuel/air at a good mixture, get it in and out fast. Keep the moving parts to the lowest weight, have the least amount of friction, and more. If you are still asking the same question, you just don't want to accept the truth

 

Here are some details you need to look at. Raptor 660cc Compression Ratio, 9.2:1, Bore 100mm and stroke 84mm. YFZ 450cc Compression 11.9:1, Bore 95mm and stroke 62mm. The YFZ compression is much higher than the raptor. Most people agree that even if the Raptor can get a 12:1 compression piston, they need to run race fuel. The YFZ uses standard fuel at 12:1 compression. Why? Head and piston design. Then you will see that they Raptor and YFZ have very similar bores. The big difference is stroke. Shorter stroke the higher the RPM's it can handle.

The Raptor was never designed to be a high rev motor, where the YFZ was. Thus it will never be able to make the sort of HP per CC that the YFZ motor will.

So how do people get more power in a Raptor motor, they add more cc's and up the compression. But it still will never be able to match the HP per cc of the 450. Just take it form us. Unfortunately that’s how motors work.