Help me jet my yz450f

[Zakradu398]

Well, I refuse to go on thumpertalk, bunch of p*ssies. Anyways. It pops horribly on decel and is hesitant in the mid range and when stabbing the throttle(AP). It has a fmf 4.1 slip on and UNi filter. Jets are stock but I think the main is a 165? High rpms feel good though so I think that's good. 1000-1200 elev. about 70*.

Thanks for the help..

[quadrider]

turn your air screw out a few more turns, but probly have to go up on your pilot jet

[chucked]

Yes I second what he/she said ^

[Zakradu398]

Okay. Raise the needle for the mid, correct?

[chucked]

Yes, but start with the pilot jet

[Zakradu398]

Thanks for the help bro. Should I just read my manual on how to adjust the accelerator pump

[chucked]

Well yea, but its not as easy as reading a book. You'll have to buy jets and try different things out.

[JAG Motosports]

u could start by setting the ap screw at 2.6 mm and safety wire the arms together. There r you tube vids that show u how to do the ap mods and of course thumper talk has instructions and vids

[Zakradu398]

If I'm not mistaken the rubber band mod is only for the older ones.

Also, I'm decent at jetting. I just wanted to make sure I was headed in the right direction ;)

[JAG Motosports]

your correct .... didnt notice the year

[Zakradu398]

Thanks anyways bro

[KXRida]

Jetting is all trial and error. What may work for another rider/machine may infact not work for you. I'm taking it you recently installed the exhaust? Usually one size up on the pilot and one/two sizes on the main get you in the right direction. It may feel ok up top but try a larger jet. Generally you want to add more fuel to the increased air flow to get the most potential out of your exhaust, but obviously a full system will yield you the most. If you're still lean/popping in the mid range an adjustment on the needle may be needed. More so towards the 2 strokes, but consistency is best. Run the same fuel, oil, ratio, and jet for the conditions. Hope that helps.

for what it's worth, IMO thumpertalk is the best site hands down for tech questions.