YFZ450 Jetting .

Quote:

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Originally posted by Quad18star
Stock pipe ?? airbox lid on or off? Temps ?? Elevation ??

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HMF full system
airbox lid off with prodesign proflow kit(foam)
airbox lid outwear
35 degrees out runs good
Live in PA dont know Elevation

Quote:

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Originally posted by cdalexct
HMF full system
airbox lid off with prodesign proflow kit(foam)
airbox lid outwear
35 degrees out runs good
Live in PA dont know Elevation

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Perfect ... thanks for posting more info .... I think the average Elevation in PA is the same as I have ... anywhere from 700ft to 1300 ft .

HMF full system with Quiet core insert
UM aluminium air box w/250R Uni foam filter,lid on
North Tenn 500ft elvation
Fuel screw at 2 turns out
165main
45 pilot
NCVQ needle on 3rd clip
94 Ultimate

Thats exactly what im running except a 42 pilot, what temp are you at?

Wintertemps range from 20 to 50 degrees.I was running a 162 until I put on the UM airbox/250R Uni.

Your like the only other person that ive seen with a 165 besides me...everybody says to try 168, and i tried that and i was WAY too rich...weird huh

I followed HMF instructions and my quad ran like CRAP.I started with the 175 main and the 45 pilot.I went to the NCVQ needle right from the start.It took about 2 months to get it to where I am now,believe me I tried all the combos.I finally ordered jets from 160 to 180(Carb parts wharehouse:macho)When I had the 170 in it ran like there was water in the gas.When I kept messing around,thought I was there with the 165 main.After going to H/M last year I realized that weasn't right either.I started to think there was a deeper problem(rectifier/electric).But I finally got the 162 in and BINGO there it was.

yeah it seems that you and i are leaner that everybody else, which is weird too...with full exhausts and filters, i wonder what is causing them to go up so high as 172 and even 180 as hmf suggests

what do you guys recommend for this setup as a good starting point

lid on
dr d slip on w/ fmf powerbomb "sx" header
cam mod
uni air filter
1200 ft above sea level
60-80 degrees
pump gas 93

from what i read about what alot of guys run i was thinking a good starting point would be

168 or 170 main ( what do you guys think)
45 pilot
nvcq needle 4th clip
air screw 2.5 turns out

anyone have a better idea for a good starting point? my quad felt sluggish at times last year and had a slight bottom end hesitation at times with the dyno junk kit and i really wanna solve that

I have a 165 main
42 pilot(stock)
3rd clip on NVCQ clip
3 turns out on fuel screw

Im at about 1000-1100 ft
and at the moment temps are around 40, i raced a 1 hour harescramble yesterday and it ran great.