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08 yz450f jetting help

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1)2008 yz450F


Temps: 70-100

Humididty:not sure, i ride cal city alot

Type of riding:Trails, c class MX, lots of hills

3)modifications (pipe,air box,motor)

Uni Air Filter

Adj Fuel Screw

Stock head pipe

FMF mid pipe and Factory 4.1 titanium


Main Jet: 160

Pilot Jet: 45

Starter Jet: 72

Leak Jet: 55

Fuel screw/Setting: 1.5-2.0 turns out

Needle/Position: NFLR-3


-Bike has decel pop (not a huge issue)

-The Bike has a slight hesitaion in the mid range, for example, if you use about 3/8 throttle going up a hill the bike will not want to accelerate, i have to give it more then half throttle to make accelerate up hills. Where as most bikes i have ridden will continue to accelerate.

-If i rev too quickly from no throttle to full sometimes it will die.

-If i gas it, then coast in neutral and rev the bike it will sometimes die(especially around corners) (someone told me its because i came off a 2-stroke, and i just need to get over that)

-The bike had a hesitaion up top too, i turned the needle to 1-3/4 and it completely cleaned up my top end, it rips now. however the bike is extremely hard to start.

6)The bike starts great with the choke on when cold, but once warm it can be tricky to start. the bogging conditions do not seem to be affected by temp, or altitude (i ride the high desert and Pismo Beach back to back.)

I got this suggestion from the forum

165 main

43 pilot


50 Leak Jet

2 turns out

Do you think this will help with my jetting woes? Im starting to get really bummed out not knowing where to start.

Thanks in advance for anyones help


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