I was going to remove the spark aresster out of the stock exhaust and remove the air box lid, i have the pro design intake witht the k&n filter, anyone know about where i should set my mains, clip,air screws, and pilots. I live about sea level thanks.

 

I am waiting for an answer to that same question. I anyone knows any jetting spec. for the raptor....please help us

Thanks

 

Do a search on raptor jetting in the yamaha form. You will find what you are looking for.

 

Where do i go for the yamaha form? What is there a web site or something let me know, thanks.

 

A good starting place would be on the FMFracing.com site. The have a chart that may help.

 

There is no single setting I can give that I can give you to make this work, jetting is something of an art. I ride at 5000'->8000' altitude, have a full aftermarket exhaust, modified airbox and aftermarket airfilter. I used a dynojet kit and right now use a 142/144 main jet combo with the needle jet on the 4th setting from the top and my air/fuel screws set at 2.5. With this setting my raptor kicks butt. At sea level I would expect to run mains at 155/160 (maybe higher). The modifications you describe are minor in terms of jetting adjustments. What does your spark plug look like? if you are running a bit lean bump up your main jets abit, run your bike at 3/4->full throttle and chop the motor and check the plug this will tell you how the main jets are doing, if the insulator is black back off on the jets, if white go up another size. the same procedure can be used to check the other jetting circuits (up to 1/4 throttle for the air/fuel screw and pilot jets, 1/4-3/4 throttle uses the needle jet). hope some of this helps

 

i have the pro-design kn filter and my main jets needed changed i have a stock
exhuast i am useing 145-150 jets and seams to run fine!

01 blu 660r