Ok so I bought a 07 couple months ago and installed a k&n, 4 of those 1" vents in top of box I had layin around and removed sliencer. So now when I go to wide open throttle too fast it will bogg and die if i dont let up but I can ease the gas. I order the fuel screw for it so I was wondering if I could adjust the air and how to line it out or should I go ahead and jet it?

 

Definetly rejet. It actually comes lean from the factory. After doing the stuff you did it's worse. Buy the next two or three sized jets. Take a look at possibly going up one size on your pilot. Will probably also need to adjust your needle. If all of this is greek to you find someone locally that knows what they are doing and get them to help you.


Buck

 

Re-jet Re-jet Re-jet Re-jet Re-jet Re-jet Re-jet Re-jet Re-jet

 

Yes you need to jet it. It's lean to begin with and you've leaned it out even more now.

If you want to blow it up, well in that case, then don't rejet. [img]i/expressions/face-icon-small-smile.gif[/img]

 

I jetted my 99 banshee before but thats all I ever jetted. What size do I need to get, i dunno whats factory in mine? And wheres best place to get them from? Thanks.

 

Try going to a 172 main jet, and a 45 pilot.

I am not sure if the 07 has an adjustable needle or not. If not, you can get a stock one from an 04 and put the clip on the 5th-6th position (as measured from the FAT end of the needle). I would also turn the fuel screw out a bit (to 2 1/2 to 3 turns out). I think the 06's had to have a hole drilled to access the fuel screw. Not sure if the 07's are the same in that respect or not???

Anyway, those settings should get you closer than you already are.....

 

I was thinking about getting the GYTR jet kit so I have everything i need. What kits you guys prefer? GYTR, FMF, DynoJet?

 

172 seems pretty fat... When i had mine w/ open air box proflow k@n and slip on hmf i was about perfect with a 46 pilot a 48 was to fat/rich and a 168 main. didn't do anything with the needle. that worked for me when i had mine it was an 05

 

I dont think he has a pipe. And 06-07's like to be jetted about 1 size leaner than 04-05's. He should start around 160

Get the gyt-r jet kit. It has the upgrade needle, jets, pilots, etc. It has instructions for 06-07 bikes with no lid and stock pipe. That should be REALLY close. Its 160 main, 42 (stock) pilot and screw.

Most yfz owners and racers hang out at another website. This site wont let me post its name. Lets just say that "yfz" owners find it to be thier "central" info source. NOONE over there uses dynojet or any other brand of jet kit. Some guys buy the individual jets, but you also need the needle. 07's dont have adjustable needles.

Also, when you have the bowl off you need to knock out the a/f screw plug. Get yourself a YZ thumb adjustable air/fuel screw. They's like 10-15 bucks. Then you can dial in your pilot a/f setting without taking your carb off. Best $12 I ever spent on a quad!

BTW: I have the gyt-r air filter kit (k&n with adapter), lid off, gyt-r pipe. I'm jetted at 165 main, NRVQ needle 4th clip, 45 pilot, 2 1/2 turns out on the screw. It's perfect at sea level and 70 degree weather.

 

i put a 210 main and a 45 pilot proflow kn filter kit open air box , pipe ,retarded the timeing on my 07 yfz450se dyono it .50hp its right on the money....i am 280lbs and i can spank the 07 lt450r with a 140 lb rider on it. with the same mods i have done... just thought i would put that in there