Started to mod it II

[Chet]

Well I just got thru with the HMF slip on and Uni Air filter installation on my 07 400ex, left the air box lid off and took it for a little spin, so far I hope when I rejet it I will feel some more zip, as it is now HMMM! I could be wrong, but I don't feel much if anything in acceleration so far. will the jetting make much of a difference. I called HMF for the jetting specs, they suggest a #42 pilot and a #152 main. any comments. sounds good though.

Chet

jetting makes a huge difference. without jetting your just running lean and making more noise. one way it was a studder the other a bog just right the front wheels in the air. it was fun when i had to rejet seeing what did what and when you get it right you will know because you should deffinately feel it. the 1st time i jetted my quad i got it spot on 1st time, did a lot of research and checked out what others had took a stab at it and it was right. then i opened my throttle up more because it wasnt opening up all the way and i had to rejet, thats when i had to play aorund some. bigger main got the top end dialed in but the needle setting needed to be played with. what i said above laps around the house started with a bog, went down a notch front wheels are off the ground when i hit the gas, went down again a studder so i went back up. I have a 42 pilot, 158 main, and needle on the 3rd slot almost at sealevel and a very warm climate and it runs perfect. your higher up and have a little less airflow so HMF is probally right with their suggestion