WR400/426/450 Jetting Database

Model (400 - 426 - 450): 2004 450

Timing (WR-YZ): WR

Main jet: 160

Pilot Jet: 42

Fuel screw (turns out): 1 3/4

Needle model/Clip position: Blue, 4th position

Airbox lid (on or off): off

Pipe: Stock w/ PMB insert

Altitude where you ride: Sea Level to 4500

Temperature where you ride: 50-90

Degree of satisfaction :applause::p:ride:

Also: leak jet - plugged, starter jet - 72, pilot air jet - 100, diaphram inserted in reverse position. UNI filter, Zyp-Ty fuel screw

I can't take the credit, but this set up is great for overall riding. The bike starts much easier and I'm not draining the battery on cold starts....

Model: 01' WR 426

Timing: Stock wr

Main Jet: 170 JD

Pilot Jet: Stock

Fuel Screw: ZipTy .. 1.5 out

Needle model/Clip Position: JD Blue #4 down

Airbox Lid: OFF

Pipe: Stock

Air Filter: Stock

Altitude: 0-3000 ft

Temp: 40-65 degrees with considerable humidity

Degree of satisfaction: :thumbsup:

Model (400 - 426 - 450): '05 450

Timing (WR-YZ): WR

Main jet: 168

Pilot Jet: Stock

Fuel screw (turns out): Zip-Ty 1 3/4 turns

Needle model/Clip position: JD Blue 3rd ring

Airbox lid (on or off): On

Pipe: Minus Baffle

Altitude where you ride: 5000-9000

Temperature where you ride: 70's-high 90's

Degree of satisfaction: Wont know till winters over :thumbsup:

Model (400 - 426 - 450): 2005 450

Timing (WR-YZ): WR

Main jet: 168

Pilot Jet: 48

Fuel screw (turns out): ZipTy - 2 turns

Needle model/Clip position: Stock

Airbox lid (on or off): Snorkel out, punch-outs removed

Pipe: Stock, baffle removed

Altitude where you ride: 100 to 4,000

Temperature where you ride: 35F - 65F

Degree of satisfaction: :thumbsup::bonk::thumbsup:

This setup has worked great all year and doesn't require me to change a thing.

Model (400 - 426 - 450):2003 WR 450

Timing (WR-YZ): WR

Main jet:168

Pilot Jet:45 (Starter jet 72, leak jet 70)

Fuel screw (turns out):2

Needle model/Clip position:JD Red 5

Airbox lid (on or off):Snorkel removed

Pipe:Stock, removed outer baffle

Altitude where you ride:2500-7000

Temperature where you ride:Vegas, so 40-90 F

Degree of satisfaction:98%

Model (400 - 426 - 450): 2005 450

Timing (WR-YZ): WR

Main jet: 168

Pilot Jet: 48

Fuel screw (turns out): ZipTy - 2 turns

Needle model/Clip position: Stock

Airbox lid (on or off): Snorkel out, punch-outs removed

Pipe: Stock, baffle removed

Altitude where you ride: 100 to 1500 FT

Temperature where you ride: 55F - 75F

No problems yet, but the hot Texas weather is coming up in a few months so these settings may change.

Model (400 - 426 - 450):450

Timing (WR-YZ):wr

Main jet:168

Pilot Jet:48

Fuel screw (turns out):2

Needle model/Clip position:#4

Airbox lid (on or off):mod

Pipe:FMF

Altitude where you ride:4200 ABS

Temperature where you ride:32-40 *C

Degree of satisfaction:very happy :thumbsup::thumbsup::bonk::bonk::bonk::eek:

Model (400 - 426 - 450): 450

Timing (WR-YZ):YZ

Main jet:175

Pilot Jet:48(winter) 45(summer)

Fuel screw (turns out):2.0

Needle model/Clip position:stock

Airbox lid (on or off):off

Pipe:baffle out

Altitude where you ride:0-2000 feet

Temperature where you ride:60-80

Degree of satisfaction:9

Model: WR450 F ‘06

Timing: WR

Main Jet: 170

Pilot Jet: 48

Starter Jet: 70

Pilot Air Jet: stock

Leak Jet:50

Fuel screw: Factory R&D - P 51A, 1 3/4 turns out

AP cover: Factory R&D - P 38 Lightning

Needle: OBDUS 4th clip

Pipe: Stock, baffle removed

Elevation: 1000

Temp: 45-75 F

Gray wire disconnected, air box snorkel removed, YZ throttle stop, ACV disabled, AIS – home made removal kit.

Tall man mods: footpegs - Fastway F3, seat SDG Racing tall, handlebar risers – Ramirez

Degree of satisfaction: 10/10 :thumbsup:

This is what i ended up with:

Model (400 - 426 - 450): WR450F ‘06

Timing (WR-YZ): WR (grey-wire cut)

Main jet: 170

Pilot Jet: 48

Starter Jet: stock (not listed in the manual)

Pilot air Jet: stock (not listed in the manual)

Leak Jet: stock (50)

Fuel screw (turns out): stock (1,75 out)

Needle model/Clip position: OBDUS 4th clip

Airbox lid (on or off): off

Pipe: stock, baffle removed

Altitude where you ride: 0-2000ft

Temperature where you ride: 30-85 F (0-30 °C)

Model (400 - 426 - 450): WR450F ‘05

Timing (WR-YZ): WR (grey-wire cut)

Main jet: 160

Pilot Jet: 48

Starter Jet: stock

Pilot air Jet: stock

Leak Jet: stock

Fuel screw (turns out): zip-ty (2,00 out)

Needle model/Clip position: Red #4

Airbox lid (on or off): off

Pipe: SuperTrapp IDS2 Race - 16 disks

Altitude where you ride: 500-2000ft

Temperature where you ride: 80-105 F (30-46 °C)

Boyelsen Acc Pump

14/45

Satisfaction 0-10 : 8

It too hard to start above 90 F , too rich in the rapid acceleration.

Tocantins, Brasil __________________________________

Model (400 - 426 - 450):2003 WR450

Timing (WR-YZ): WR - Gray wire cut

Main jet:170

Pilot Jet:45

Fuel screw (turns out):Zip-Ty1.75

Needle model/Clip position:JD Blue/4th

Airbox lid (on or off): off

Pipe: ProCircuit 496

Altitude where you ride: sea level to 2500ft

Temperature where you ride: 65 - 90

Degree of satisfaction:6+

Great mid-range on up, but stutter at low speed-constant RPM. Tried tons of combos and same result. TPS plugged or uplugged = no difference.

Model (400 - 426 - 450):2006 wr 450

Timing (WR-YZ): WR

Main jet:170

Pilot Jet:48

Fuel screw (turns out):1.75

Needle model/Clip position:JD red on the third clip

Airbox lid (on or off): off with cutouts removed

Pipe: Stock with no baffle

Altitude where you ride: sea level 1000'

Temperature where you ride:40-60 right now Degree of satisfaction:8

I gave it an eight because I wanted to leave room for improvement. the bike does rip though. It took me a long time to get it right, my setting on the needle is so much different than what the JD kit or the data base suggested. I had to try about 7 different settings before I could get rid of my mid range sputtering. Finally switching to the red needle and backing it down one clip at a time until I got to the third clip, now I can pull easy second gear wheelies and third gear with a little yank on the bars. Settings will change once I get the money for the Pipe I have been eyeing !

Model:'03 WR450

Timing: WR

Main Jet:168

Pilot Jet: 48

Starter Jet: 70

Leak Jet: 40

Fuel screw (turns out): 1.75

Needle model/Clip position: JD Blue 3

Airbox lid: On w/ snorkel removed, stock filter.

Pipe: FMF Q, Stock header pipe

Atitude where you ride:800-4500

Temperature where you ride:50-75

Degree of satisfaction: Lower Elevations to @2500 - Fantastic, then gets fatter to 4500, but still great power throughout. I weight 175 filly outfitted, so not a big load. Easily lifts in top of first 3 gears.

Additional Info: NGK CR8EK's made starting easy with no/little higher alt. fouling, ACV operational, AP cover mod (self, sim. to Boyesen), no bog, sputter, flat spot, slight popping higher alt., no backfire.

Model (400 - 426 - 450): 2006 WR450F

Timing (WR-YZ): WR

Main jet: 168

Pilot Jet: 48

Fuel screw (turns out): Stock? Not sure, didn't touch it

Needle model/Clip position: Stock

Airbox lid (on or off): Stock

Pipe: all stock, baffle removed from silencer.

Altitude where you ride: 2000-4000 ft.

Temperature where you ride: 45-85 degrees

Degree of satisfaction: :thumbsup: It's my buddy's bike. It seems to have a lot more power now that we did the baffle mod and rejetted. Had a little problem with hesitation at the start, but then once it warmed up it seemed fine.

By the way, the stock jets are 165 main 45 pilot, that doesn't seem to be listed anywhere.

Model: 2006 WR450

Timing (WR-YZ): WR cams with Grey wire cut

Main jet: #168

Pilot Jet: #48

Leak Jet: standard

Fuel screw (turns out): Zip TY, 1 out

Needle model/Clip position: JD Red #5 position

Air box: side still on but snorkel out.

Filter: Twinair + PC Racing filter skin

Pipe: White Brothers E2

AIS off

YZ Throttle screw

Altitude where you ride: sea level to 350 feet

Temperature where you ride: Now 22 to 32 degC

Model : 2006 WR450FV

Timing (WR-YZ) : WR

Throttle Stop (WR-YZ) : YZ (comes with GYTR AIS removal kit)

Grey Wire Cut (YES-NO) : Yes

Main jet: 168

Pilot Jet: 48 (comes with GYTR AIS removal kit)

Starter Jet: Stock

Leak: 40

Fuel screw (turns out): 1.75

Needle model/Clip position:

GYTR / 4th clip from top (comes with GYTR AIS removal kit)

Airbox lid (on or off): snorkel removed, side cutouts removed

Pipe: Pro Circuit T-4 slip-on

air filter: GYTR Dual Stage Foam Filter

Altitude where you ride: 1500 - 4000 ASL

Temperature where you ride: 50 - 95F

Air Induction System (AIS) :

Removed using GYTR AIS Removal kit.

Yamaha Part number (GYT-5TJ93-69-00)

Degree of satisfaction: 10!! Runs superb!! No hesitation, very crisp throttle response and starts very easy! :crazy:

Model : 2006 WR450F

Timing (WR-YZ) : WR

Grey Wire Cut (YES-NO) : Yes

Main jet: 165

Pilot Jet: 48

Air Jet: 65

Leak: Stock

Fuel screw (turns out): 1 1/2

Needle model/Clip position: OBDUQ - 4.

Airbox lid (on or off): snorkel removed

Pipe: Full titanium Leo Vince X3

air filter: TWIN Air

Temperature where you ride: 10 - 30 ´C

Finally got it right today. 165 Main, JD Red#4, 45 pilot, 1.5 turns out, other jets stock. It's mid 80's during day and mid 40's at night, no humidity and 4,000 foot elevation.

Model (400 - 426 - 450): 06 wr450f

Timing (WR-YZ): yz

Main jet: 168

Pilot Jet: 48

Fuel screw (turns out): 1.25

Needle model/Clip position: JD red needle 5th clip

Airbox lid (on or off): on (side opened up and baffles removed

Pipe: fmf 4.1 sl

Altitude where you ride: 1500 +/- 400 feet

Temperature where you ride: this jet setting tested from 65 to 90 degrees

Degree of satisfaction: very satisfied. No bog, hestitation popping or farting. Pulls strong throughout the rpm range.

Additional mods :JD powersurge accelerator pump kit with 40% oring with 40 leakjet

Mods for both bikes: Grey wire disconnect, airbox mod, yz throttle stop & AIS kit. I adjusted the slide height to the recommended 3.1mm and removed all the play from the accelerator pump linkage. All other jets are stock unless otherwise mentioned.

Matts Bike with Moose racing (aka dynojet) kit, boyesen pump cover with JD 80% oring & 60 leakjet.

Model (400 - 426 - 450): 05 wr450f

Timing (WR-YZ): yz

Main jet: 150

Pilot Jet:48

Fuel screw (turns out): 1.0

Needle model/Clip position: 4th clip

Airbox lid (on or off): on but baffles removed, side cover cut

Pipe: whiteborthers mx4

Altitude where you ride: same as above

Temperature where you ride: same as above

Degree of satisfaction: very satisfied. Told me he had an occassionally sputter while cruising at a steady speed, but it only happened a handle full of times during the 3 hours he rode. Bottom end is strong and hits hard, and pulls clean throughout the rpm range.

As Burned stated in one of my previous post the moose racing needle is much richer down low. I had to install a 60 leakjet in matts bike to eliminate the off idle hesistation. You can still stall the bike, but there is no reason to wick the throttle that hard while riding. I found with the JD kit I installed the 40 leak jet to eliminate my off idle throttle issue.

I would like to say Indy's guide is nearly spot on. I thought I may have to richen my main a bit after installing the fmf pipe, but I didn't. Both matt and I are really happy with both products.

If anyone is wondering about the sound of the fmf factory 4.1 SL Natural Titanium it sounds pretty good. Its defienately louder, but has a nice deeper sounding tone to it. The WhiteBrothers mx4 matt got is just plain rude to the ear drums.

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