Ok you YFZ Guys!!

Heres the scoop... stock 04 YFZ with a UNI Pro Flow filter kit (Lid ON) and Two Brothers full exhaust system. Put the jet that came with the pipe kit in and now it will pop and spit unless I put the choke on.

Soooooo what do I do? Anybody have any jetting tips for this set up???

Oh and itll be going to G and Dumont so elevation and temps should be close enough for same jetting.

Thanks in advance for all your great information!!!!!!

- J

I would run a 172 main, 45 pilot, 2 turns out on the fuel screw, and NCVQ needle on the 3rd clip.
Just go to your local shop, and ask them for the jets for a YFZ450. You need a 45pilot, and a 172 main jet. Then tell them you need the needle from an 04 YZ450. It will say NCVQ on the needle itself if you look real close. Count the slots on the needle (for the clip) from the top down. You want to be on the 3rd from the top.

x2 and take the airbox lid off

Thanks guys!!!!! I pulled the carb and found that the jetting was exactly that! What I also found was a coil plug that was not connected all the way so it was melted and not making contact with the spark plug and also the head pipe was really loose.

All fixed and runs like a top!!

Thanks again!

- J

X3