Full or Slip on?

[Fralick #81]

I know this has been covered before but i want your opnions on the yfz 450R. Im looking to get an exhasut and want to know if the full system is worth the extra money? Also will i need a fuel controler for just a slip on or even the full system? Also what pipe do you guys recomend? Thanks, Jon

[Vampire2800]

You're right. It has been covered. Moving on.......... It's almost always better to go with a full system. Why? The head pipe is larger with some of the aftermarket pipes. Take the GYTR for example. The head pipe is not much fatter, but it IS still fatter. Thus, allowing more air to exit the engine. I went with the GYTR full system because it's tuned specifically for the new yfz450R's. In my opinion, nobody knows the quad better than the people that built it, so I trust what they make for it. Motoworks makes a good pipe. So does Yoshimura. Take your pick. With regards to the fuel controller, check the maps first before you decide. This may help your decision a little bit.

[yamahahaha]

u dont need a fuel controller, or anythng. my full system yoshimura works great! and after buying a full system i wouldnt buy a slip on

[Vampire2800]

+1

[rdstoner]

the only reason you would need a fuel controller is if you paln to run a high flow filter with the air box lid off. if you leave the lid on the FI will adjust itself to the full system but it cant make major changes.

[bmerriman12]

lid off = more air flow which = more hp

[yamahahaha]

with my full syatem, i have the box lid off and have a k&n. and it works great

[rdstoner]

you might want to check your plug and see how lean yyou are running the ecu wont adjust itself that much to compensate for the extra air that you are putting to it. that is why you need a controller