I just got off of the phone with Allen of CT Racing. I just wanted to confirm that I was reading their dyno chart correctly and that it was Rear Wheel Horsepower and it was.

He, just as I am, is amazed at the amount of power that the Raptor has to be tapped. He said that without freeing up the air intake, they could only gain about 8 hp with a pipe, but by running with the lid off, jetting and their pipe, they are hitting right at 50 and expect it to go over 50 wheel HP once K&N makes a filter for it.

He said that the DS650 makes as much as 15 HP over stock at 3500 RPM, but that it only peaks with about 2 hp more than stock. This is why it really shocked him that the Raptor gained 17 HP over peak as well as a lot over the entire power spread. He said that the 5-valve configuration really makes things happen when it can get enough air.

Also, the graph on their website looks like the stock pipe has more power before 2,400 RPM, but he said that was because he failed to pin the throttle on the piped Raptor until that point.

He also said that the Raptor is the only bike they've ever tested that makes the most HP using the disks in the SuperTrap instead of the open turn-down spout and that they include extra disk so that you can use 16 disk to extract maximum HP out of it!

I just thought I'd share what info that I know.

He said that they are selling faster than they can build them, so don't delay if you want one.

 

If you believe that taking the airbox lid off and adding a pipe too a 4-stroke engine will result in a 17HP gain. I have a bridge I'd like too sell ya.

More air in and an easier path out will result in more horsepower. But if your stuck with a stock engine, these mods don't do squat. Think about it. You still have the stock carbs, stock piston(low compression), stock camshaft, stock ignition timing, stock CDI, and the head and valves haven't been cleaned up. Even with all of those mods, you will be very lucky too pick-up 17HP without a bore/stroke kit.

Here's a tip........ Aftermarket companies like too pad their numbers alittle too increase sales. I see some major padding here.

Why don't you ask how this "kit" adds all of the extra HP? Inquiring minds want too know....

 

However keep in mind that something is only as good as its weakest link. If the other components of the engine were being choked down because of the pipe and more importanly the air box then its very possible to see increases like that with stock parts.
Dave 250R (Still the KING)

 

Let's take a look at how a 4-stroke exhaust pipe works.

4-stroke Exhaust 101

As a 4-stroke engine enters the exhaust phase, the piston move upwards, the exhaust valves open, and the spent gasses are pushed into the pipe. Not all of the spent gases get pushed into the pipe and some stay in the combustion chamber. A properly designed 4-stroke pipe, "sucks" all of the spent gasses out of the combustion chamber on the exhaust stroke, so that only "fresh" mixture is available for the "power" cycle. Result.....more power.

4-stroke pipes generaly add 1-2HP, depending on the engine.

On the intake side, removing the airbox lid will improve throttle reponse and make it easier for the engine too pull more air. But if all of the variables inside the engine remain constant. The need for more air is very small.

 

Ok, then... think of it this way. Take a Chevy 454, cammed, flat top pistons, MSD ignition, all the bells and whistles. This motor is going to put out quite a bit of power. Now, stick a rags in the carb and the exhaust. I guarantee that it will have very little power, if it runs at all.

Now think of the Raptor's motor as the 454 with the stock airbok/filter and pipes as having rags in them. No power because there is no air. No air, means no fuel. No fuel means nothing to explode to push the piston down. The CT pipe and filter kit are simply taking the rags out and letting the motor make the power it's capable of.

 

So what you are saying is that Yahama has a very poor design.
If the intake and exhaust are designed this way, I wonder what other parts of the machine are also second rate?
Just something too think about......


ps. I personally do not think that the Raptor is junk. I am just trying too prove a point about these outrageous HP claims by certain aftermarket companies.

 

Yamaha designed the internals of the motor with performance parts. To limit HP out-of-the-box they INTENTIONALLY gagged the intake and exhaust, for safey/liability reasons. This isn't so bad, because it is fairly easy to modify. It looks to me like the stock header pipes are narrower than the exhaust ports.

 

Scooby,if the valves are bigger than the exhaust ports, this won't be a bad thing. It is almost like a tourque stuffer which makes the exhaust flow fast because of some guys law of motion(haha i forget who). Butanyways this may be why yamaha did this is to increase flow and get the exhaust out faster but that stock silencer has got to go!!!!!! First off I can;t hear the engine rpms so i dunno when to shift and also from the cut open view of it that thing sures looks restrictive. Just replacing the silencer would do wonders!! I hope Team Alba will come out with a airbox lid for the raptor like they do for the warrior and banshee. The lid makes the airbox water proof but gives as much air as an open airbox. That sounds like my kinda airbox lid!!I also wanna get a Pro Design Air filter setup since the yamaha design is donkey poop. My filter already fell off!!

01 Raptor
00 Warrior <-- Selling in NJ
00 Wolverine

 

Yamaha doesn't have a poor design, but a responsible and safe one. They don't want a thousand law suits so they tuned down the engine. The thing bash said about the 5 valves giving the engine more capability than other 4 strokes does make sense.

 

Oh god, They toned down the thing due to saftey and law suits? Come on now. So all the disclaimer stickers all over the bike are for decoration?Think about it, would you market a bike you couldnt modify? If somebody told you you couldnt do a thing to this bike its built to its max, would you buy it?