Everyone knows that the 660R has plenty of untapped power. Through many test it has proven to respond better to upgrades as compared to its rivals. A simply upgrade like an Air Box mod and Jet kit does wonders for this beast. I wonder why Yamaha did not design a better air box and proper jetting to make this machine further distance itself from its competition? I know during the Muscle Car war many manufactures would “DE-Tune” their cars to eliminate hefty insurance premiums but with ATV’s we are not required to have insurance so what was Yamahas motive?

I am by no means a professional in ATV power and have to depend on what I read so if my previous assumptions are incorrect please do not flame me.

I believe with a better air box design and more appropriate jetting then we would not have to here the: “Man you have 260cc more than me and you barely beat me.” When in fact the smaller bikes are nearly maxed out when compared to the gains you get from the larger displacement bike upgrade to upgrade.

I also have a problem due to the fact of little experience launching my Raptor and controlling all of the power. I rode one of the smaller bikes the other day and was able to launch harder; meaning give it more throttle as I dumped the clutch, because it was not as “Tourqey Feeling.” I am not saying it pulled harder only that I could give it more throttle as compared to my Raptor. I generally race smaller quads from a rolling start to eliminate the dead start driving handicap I have. When I learn to launch on full throttle and keep the front down then I would like to see what I could do to the smaller bikes from a dead start.

 

I might be wrong but I think quads have to meet certain emission levels in stock "selling" form.

/NotuRaptor

 

Well i can answer your question with more factual data then I can question some of your statement.

A quad manufacturer builds as economically as possible to target as large an audience as possible. Then once that is met they have to put a machine in place that is easy to maintain and is safe. Yamaha does not provide the tweak performance innovations you outline as their marketing and research tells them the bulk of the buyers wouldnt pay the extra cost associated with the upgrades
... their view is that their cost analysis shows an ideal setup and they figure if the purchaser wants the upgrades they have the option to go purchase it...making their 3rd party supporters happy and voiding warranty (sometimes) cost. Also, when you increase the performance capabilities on a machine you increase the probability for increased wear and abuse...these are items the accountants have also figured in the production setup and warranty work to maintain the machine. Now on a little more positive note...also have talked to a rep that feels if the person is that into performance then he will want to set it up for his specific need (racing, sand, trails, etc...)...in which case many performance tweaks could go several different directions in which the manufacturer could never meet. His view was give them a stock machine at a good price and let them create what they are specifically looking for with what they specifically want (was not a yamaha rep by the way). The Raptor doesnt have to go 80 mph in the stock form to be considered the fastest... it just has to beat the competition...and for now, as detuned as it might be it does that...Kawi did the samething with the v-twin...it only has to go slightly faster then the closest competition to get the label "The Fastest"...despite what the machine is capable of doing. So to summarize above they dont do it because of cost, warranty COST, not sure COST meets demand, dont want to step on 3rd party supporters, safety (to some extent), gives (some of) them an out on certain warranty work, mets objectives in current production setup (very simplified outline). They look at it as a business where we look at it as an exciting hobby.

Cost Example:
Increase air intake making different fuel mixture causing a bigger demand on exhaust system...to take full advantage of improved air intake they need to improve exhaust and jetting requirements. Not counting research and development cost, regulation shuffle with noise and emissions, this will add another 100-200 dollars cost to the machine in which case a true enthusiast will probably modify both the air intake and exhaust again (how they look at it). Research shows an additional $150 dollars added to the machine has it lose additional buyers to the midsize machines or making it less attractive in the big bore market dropping overall market share. They have studied these scenerio's trust me. Sorry for the long explanation...goes far deeper then this I just dont know if I emphasized the points I was trying to make very well.

Now for the Raptor being more responsive to mods then other quads I have heard different. Now before this goes any further I am not doggin the Raptor as the 660 single banger is a wicked power plant. But, what feedback people have provided me is that the Z400 is probably the most responsive to mods of any engine in the sport arena (banshee excluded as I have heard very few talk about it). That in stock form the Raptor is far stronger but the Z closes ground as they mod (both machines doing mod for mod). Anyone else have anymore info on this...I ride a 650 prairie and love it...but was thinking about getting a second quad just as a duner (I am in Utah). Again, info i have is just feedback from riders and not hard core factual data. I would be interested in others opinions as well...

 

I agree with everything that Bosox07 said except the fact that the Z-400 is more receptive to modification. In the March '03 issue of Dirt Wheels there is a Z-400 exhaust shootout. All of the exhausts (15 of them) made between 5% and 10% more peak horsepower than stock.

In last year's February '02 Dirt Wheels Raptor pipe shootout, all of the aftermarket pipes made between 20% and 35% more power than stock.

It is simple math. Whoever told you different is wrong.

Also, by going with a 450cc kit (12.5% increase in displacement) and some port and polish work, you could probably get the Z up to the mid 40s for HP. An increase from stock of about 50-60%. Now if you increased the Raptor's displacement by 12.5%, to about 740cc. You could easily double the stock HP numbers, 100% increase!

1+1= Raptor gains more from mods

What do you think guys? Does it add up?

RR1

 

How do you figure? Mid 40's is not an increase of 50-60%! If you increase by those cc's you would have 60+ HP!! Depending on what Dyno numbers you use, a stock Z has anywhere between 29 & 32 HP. Even if it was only 25 HP it's more than mid 40's!! That must be some good shiznit you're smokin'!!

 

29hp * 1.50 (50%) = 43.5

Basically a 50% increase in HP means you have your starting HP and half (50%) of the starting horse power added back. To get 60+ HP from a 29HP start you would have to add 110% back to the original.

I was under you same theory Raptor Racer. I do not have a club, dyno, or anything else so I have to base my opions on what I have read in articles.

 

I was pondering this: Would there be a market for a Raptor sold with a 11:1 piston, performance cam and a heavt duty clutch and sold without an exhaust and no suspension (shocks, a-arms, swingarm) and they could keep their crappy skids and graphics also. No tires or rims just spindles and brake components. And no warranty. How cheap do you think they could sell one for?