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Leo
08-24-2001, 02:54 PM
A DIY jetting article was sent to me.. What I want to do is compile a list of common mods + what you are running for jetting... I'm going to make a list of as many setups as I can, so people can use them as a baseline when jetting...
So, what I need is for you to list;

if your quad is a 300/400...
engine mods...
airbox mods...
exhaust mods...
what air filter you run...
rough altitude you ride at...
main jet (specify OEM or dynojet)...
needle position (specifiy OEM or dynojet)...
pilot jet size...
pilot screw position...

Please include as many details as you can.. I think if we can come up with a decent list of mod/jetting combos it will give everyone a rough idea of where to start when jetting there quads!

Thanks to everyone who helps!

Leo

400exRacerX
08-24-2001, 04:12 PM
400ex
stock engine, except for clutch mods, wich are listed in my signature
outerwear airbox lid
white brothers silencer with open end cap
powerbomb head pipe
K&N filter
roughly 700ft above sea level
158 main jet, OEM style jet
needle is at stock position
42 pilot screw, OEM style
pilot screw is at stock position

MOFO
08-24-2001, 04:57 PM
Ok, here it goes...


400EX
-FMF Powercore IV SA
-Stock head pipe (for now)

Airbox Mods
-(6) 1" Uni filter vents
-Uni Filter airfilter

1246 ft above sea-level (airport 3 min away)

MAIN JET: 155 Summer - 160 Fall, Winter and Spring
I run this combo because my quad runs rich during the
hot summer days (air less dense). Yes I am very picky :) Anyone else notice their quad gets more air when its cooler out?

PILOT JET: 40 (going to change to a 42)

NEEDLE JET: STOCK (for now...going to move clip one position)

AIR/MIX SCREW: Went to dealer to use their special screw driver to adjust it. Have it adjusted for the highest idle, then back the idle down to stock RPM's via idle adjustment screw. (recommended by head mechanic/engine builder)

The reason I wanted to use their screwdriver is that when I had my quad warmed up, I could not get a regular screwdriver in there to adjust it without burning my arm on my exhaust. And I'm too cheap to buy that extended/flexible screwdriver :)



As you can see I am still tweaking my quad, but it runs GREAT as is. Just a tad rich, exactly how I want it.

Eric

Leo
08-24-2001, 06:25 PM
Thanks guys...:D

Let's have some more!

Leo

08-24-2001, 07:20 PM
400EX
no engine mods
4"x8" hole in airbox lid with foam filter attached
Pro-Circuit T-4 exhaust with stock headers
stock air filter
550' altitude
165 keihin main jet
stock needle position
stock pilot with stock setting plus 1/2 turn out

soon to increase pilot to 40 or 42
this bike runs strong
Thanks to all who have helped !
John

Winged Warrior
08-24-2001, 07:51 PM
400EX uni filter/148 main oem/40 pilot oem/WB slipon/oem everything else/altitude ,who the heck knows-somewhere in the hills of
ky.:huh

4punksdad
08-25-2001, 07:22 AM
>2000 400EX
>no engine mods
>2 different airbox lids, both modified & pre-filtered
>Modified stock exhaust silencer (removed s/a & rear baffle plate)
>stock foam air filter
>elevation= 500 feet
>165 main jet
>stock needle position
>stock pilot jet
>stock screw setting

08-25-2001, 08:01 AM
95 honda 300ex
stock engine
cobra silencer and headpipe
k&n filter w/ outerwear
stock airbox
130 oem style main
air/fuel screw turned once more in than stock
stock pilot and clip position
800 ft elevation

Leo
08-25-2001, 03:06 PM
keep the setups coming :D

Leo

400exBro
08-25-2001, 03:33 PM
2001 400ex
White Brothers e-seris s-bend pipe
K&N filter with pre charger
4 7/8inchs air box holes
160 main dyno jet
3rd notch
no engine mods
around 1000 feet

400grl
08-25-2001, 04:01 PM
2001 400EX

White Bros. E-Series Slip-On (running 12 disks with endcap off)
14-tooth front sprocket
Stock air filter
Stock lid (for now)
Stock jets, settings, etc.

Live in Phoenix - you'd think I'd know my altitude, wouldn't you?

Have extra 142 main jet for riding at 7,000 feet.

skemp
08-25-2001, 07:10 PM
400EX
...no engine mods
...3 - 1" holes in lid
...White Brother's pipe
...K&N
...~800ft.
...172 Keihin main
...3rd notch on Dynojet needle (soon switching back to stock) needle
...stock pilot
...3 turns out

knighttime
08-25-2001, 08:14 PM
(6) 1" filtered airbox holes, unifilter, FMF 4Q muffler and powerbomb header

160 main (may go bigger, but runs good now)
42 pilot
2 1/4 turns out
tweeked the throttle stop screw
stock needle jet position
1200 feet (was 1600, thanks Eric)

MOFO
08-25-2001, 10:02 PM
Mike,


Where did you get 1600 feet? Just wondering.... I called a pilot at the airport and he said 1246. :blah


Eric

quadfamily
08-25-2001, 11:13 PM
300EX
only engine mod is Sparks advance flywheel key

Powroll head pipe

400EX stock muffler with three 3/8" holes in the baffle

choke plate and shaft removed

K&N filter

Outerwears airbox lid

20" Razrs and stock gearing

120 feet above sea level

135 main jet (Keihin)

42 pilot jet (Keihin)

stock needle with clip lowered one notch more than stock (3rd notch I think)

Will be installing 11:1 piston soon

nakomis0
08-25-2001, 11:49 PM
Mods in signature (except FCR)
no lid on airbox
stock pilot jet
needle position second notch from bottom (K&N jet kit)
178 main (K&N jet kit)
Michigan elevation?
13 disks on exhaust

Still playing with the FCR carb tuning, I'll let ya know when I get it right.

knighttime
08-26-2001, 04:17 PM
Originally posted by VWVR6
Mike,


Where did you get 1600 feet? Just wondering.... I called a pilot at the airport and he said 1246. :blah


Eric

I thought u wrote 1600 ft. Must have been the cold malted beverages.

Guy400
08-26-2001, 04:25 PM
For altitude check out www.topozone.com

Butler, PA is listed at 1040ft.

MOFO
08-26-2001, 04:57 PM
Originally posted by Guy660R
For altitude check out www.topozone.com

Butler, PA is listed at 1040ft.

depends on where you are at in Butler...where we live (3 min from airport...) field elevation is 1246ft. That number (1040) might be an average for all of butler county. We do have some hilly terrain....

EDIT: I just checked that site, it looks like that elevation is for the actual city of Butler....we dont ride down ther LOL...


Mike....LOL, I'm surprised you got that close when drinking adult beverages... ;) I know I wouldnt even come close LOL!


Eric

4punksdad
08-26-2001, 05:06 PM
Originally posted by Guy660R
For altitude check out www.topozone.com

Butler, PA is listed at 1040ft.

thats a cool website..........but I question its accuracy.........I checked 2 towns in NY that are less than 15 miles apart (no steep hills in between) and they list the elevations at 300' difference.......seems hard to believe. When I was a kid I would ride my bicycle back & forth in a day & I don't remember any 300' inclines or declines :o

They did list our town here in VA within 40' of the actual evelvation at my house.

either way, close enough for jetting a bike!

400ex Magnum
08-26-2001, 07:38 PM
400ex stock engine
stock air filter
No airbox mods (yet)
640 ft elevation
Pro Circuit T-4 Pipe

Jetting:

155 Keihn Main Jet
Stock Pilot and needle position


Seems to be a little rich based on my plug color. I plan on adding uni filtered vents one at a time until I get it leaned out a little.

08-27-2001, 06:04 PM
-Supertrapp IDS2 Pipe w/9 disks
-155mj
-6 1" uni airbox vents
-pilot screw turned out 3/4 turns from stock.

I will soon get a uni filter and try a 160mj.

also, question for the more mechanicly inclined people. I was taking out my main jet one day and along with it was a long skinny tube which has tiny holes in it that I think the needle slides in and out of. There in a lock nut at the bottom of the tube. Does it matter where the position of the nut is? I forget what it's setting was. Does Varying the position of the nut act as an adjustment for the needle? I am gussing the main was tightened too much and the needle jet holder(?) came out.

Leo
08-27-2001, 08:09 PM
yup, it's the needle jet holder...

I believe you just snug it up, then tighten down the lock nut to hold it in place as it just holds the jet needle up in the body of the carb, but I'm not 100% sure on this, but it appears that way looking through the service manual.

Leo

Stunz
08-28-2001, 06:32 AM
Twice, that same peice came out on me. I used the same method that Leo used in replacing it. The manual only shows a picture of it, no instruction on how tight it should be or what it is for.

"Snug" works for me, then tighten that lock nut.

#77
08-28-2001, 04:02 PM
1996 300EX
Engine: .040 bore, 13:1 compression, stock carb, supertrapp E.A.R. pipe. Running 8 disks, have to keep it quiet!
Intake: No airbox lid year round, K&N air filter with outerwear.
Altitude: approx 593ft.
Main Jet: stock style, 130 (summer) 135 (winter).
Needle clip: stock position
Pilot jet: stock
Pilot screw: stock setting

Engine runs crisp, surprisingly few problems.

papaw
08-28-2001, 07:17 PM
1999 400ex,
11:1 416 wiseco
xr400 cam
oversized intake valves
stroker sx-1 full exhaust
ported and polished head
3 angle valve job
k&n filter and outerwear
no airbox lid
897 ft. at cincy airport (maybe higher for the winged warrior farther south,whats up scott!!!)
210 main
48 pilot(too rich though)
choke removed
3rd clip on needle
p.s. i personally think it does make a difference on the needle jets
position of how far you screw it in to the carb.mine has came before also but probably not enough to make that big a difference.i'd say you could really fine tune a carb with it though!

canadian400ex
08-28-2001, 08:12 PM
No engine mods
Stock foam air filter
Stock Jetting (plug looks perfect.)
Big Gun race series slip-on
Just a little above sea level, I beleive.
Stock needle setting
Stock air screw setting
Stock air box
Stock air box cover-No mods.

Wheelie
08-28-2001, 09:04 PM
2000 400ex

White Bros E-Series Slip-on
K&N Filter
Large Hole in Airbox Lid

160mj
Stock Pilot with clip lowered one notch

Thinking about going with a 40pj and 162mj

Edited--Contrary to what I posted, I just changed my jets to a 40pj and a 158mj, I found the main circuit to be a hair rich. I think I have it spot-on now. Still Stock pilot needle with clip lowered one notch.

Dune Surfer
10-12-2002, 10:47 PM
Jetting is listed in my sig.

QuadRacer041
10-13-2002, 04:12 AM
400ex:
bone stock motor
full lrd exhaust
k&n filter
no air box lid
white bros ign. box
not sure what my elevation is, im in nj
170 main
stock pilot

methyman
10-13-2002, 06:01 AM
2002 400EX
HMF full exhaust system
K&N filter with outerwear/no airbox lid
FCR 39 mm carb 50 pilot 170 main clip in middle
Curtis Sparks advance keyway in flywheel
White Brothers Ignition box
Sea level elevation
Stock motor for now
:D

RED121572
10-13-2002, 07:09 AM
With the mods listed at the bottom, my jetting goes something like this....

Stock carb.
The pilot is one size larger than stock.
The screw is tweeked a quarter turn out.
The needle clip was dropped one notch.

I have two pipes.......
E Series Slip on with 12 disk, I use a 163 main.
E Series with no disk, I use a 165 main

Those are my specs when using 94 octane pump gas.

timewass
10-13-2002, 10:59 AM
2001 400ex
engine mods... (NONE)
airbox mods... (NONE)
exhaust mods... (Pro Circuit T4 Slip On)
what air filter you run... (UNI)
rough altitude you ride at... (1500 ft.)
main jet (specify OEM or dynojet)... (160 OEM)
needle position (specifiy OEM or dynojet)... (stock OEM)
pilot jet size... (stock)
pilot screw position... (stock)

VegasEx'r
10-13-2002, 11:34 AM
quad: 400ex
mods: 416 11:1 piston, Hot Cam stage 2 cam, port & polish (like a play port & polish), 6 degrees advanced timing
airbox: removed, choke gone also
exhaust: Big Gun full race
air filter: K&N w/ outerwears
rough altitude: 2000'
main jet: dynojet 170
needle position: dynojet #3
pilot jet: 38
pilot screw: 3.5 turns

crookedeyemoto-x
10-13-2002, 02:47 PM
2002 400EX

White Bros. E-Series slip on

grinded welds in stock header

K&n air filter with no air box lid

ported head

11.1 piston 416 kit

42 pilot

185 main jet

went up one notch on clip from stock

crookedeyemoto-x
10-13-2002, 02:49 PM
2002 400EX

White Bros. E-Series slip on

grinded welds in stock header

K&n air filter with no air box lid

ported head

11.1 piston 416 kit

42 pilot

185 main jet

choke has been removed

race cam

went up one notch on clip from stock