2007 yfz 450 Got some questions

[glanzeryfz]

im new to the forum and i just got a few questions.

i just bought a 07 yfz 450 about 1 month ago. i have put on a k/n cone intake with the adapter to eliminate the screen. GYTR exhaust slip on (cant think of the number off hand) and i upgraded my spark plug to a NGK9. im just wondering did i go the right way with the plug or did i have to go the other way to a 7. Should i jet for the exhaust? and has anyone ran the big gun or ProCom cdi boxes? Which one is worth it? thanks for the help guys

[leveldrummer]

yes, you absolutely need to rejet for the exhaust and the k&n, yfz's are very lean from the factory and basically run like crap stock. throwing some jets in it will awaken a whole new animal that you have never seen before.

[daddio]

Go with the cr8eix plug, and fatten up your jetting. The GYTR cdi box is the best and most reliable of the ignitions.