2006-07 YZ450F User Jetting Database

2006 YZF450 (posted from Burned)

I can sya one thing for sure,the stock yzf jetting will be super lean at sea level.

This bike ended up with a 48 pilot jet a 162 main here at 5500 ft.

It will be able to stand a 158 in the summer.

At sea level you will need a 48 pilot and 170-172 main jet.

2006 YZ450F

-Pilot Jet 48

-Main 170

-Needle stock

-2.25 turns out fuel screw

~400 feet elevation

stock pipe, twin air filter w/no toil oil

'06 YZ450

-Pilot Jet 48

-Main 170

-Needle stock

-2.00 turns out fuel screw

~400 feet elevation

stock pipe, twin air/stock air filter

I have a 2006 YZ450. I had the jetting on a dyno. We could not get it to crisply with the stock needle. We put in a NCYR needle, and with the clip at #2, 160 main, 45 Pilot, Fuel Screw at 1.75 it runs great. I think all you guys that are haviong trouble with th '06 and trying to get with the bigger pilot should look into replacing the needle with the above profile needle.

Here is my 06 jetting for Georgia/Alabama.

Winter temps 45-60 degrees w/ medium to low humidity - (45% - 10%)



1.5-2 out Fuel screw

Probably go to a 168mj for the summer - will try Quickshot soon :thumbsup:

06 yz 450

4000-5500 ft

Temp is around 30 (this is throwing things off a little)

160 main

45 pilot

drop the needle one position

fuel screw 1 3/4 turns

Otherwise, everything else is stock...for now.

Model: 2006 YZ450f


Main Jet: 170

Pilot Jet:48

Starter Jet: stock

Leak: stock

Fuel screw: stock

Needle: stock

Air box: Moose filters

Pipe/muffler: Stock pipe with PMB S/A & silent insert

Altitude: 3000-3400 feet

Temp:current 40-60F

Humidity: ? unkown but I race in the high desert so I am assuming it's low most of the time.

I will add my new fuel screw and do some trials with the pilot jet and post my results

Model: 2006 YZ450f

Edit Revision:19/04/06


Main Jet: 170(stock is 160)

Pilot Jet:48(stock is 42)

Starter Jet: stock

Leak: stock

Fuel screw: scotts t-handle, 2 1/2 turns out

Needle: #5 clip (I richer from stock) stock needle

Air box: stock filter, no toil

Pipe/muffler: Stock header, stock silencer

Altitude: 4000ft-5000ft

Temp:current 10-15 degrees celcius

Humidity: dry 30%

It's the best the bike has ever run. No hesitations, no bog off bottom, started well. I never messed with the jetts or fuel screw during the ride because i was smiling too much!

This setup doesn't make sense to me. I think I should have been leaner than the rest of you with these settings.

I'm just waiting on my smaller leak jet to get a richer ap squirt...that should do it!

Model: 2006 YZ450f


Main Jet: 165

Pilot Jet:45

Starter Jet: stock

Leak: stock

Fuel screw: Bonez T-handle style 1.25 turns out

Needle: stock

Air box: stock

Pipe/muffler: Stock pipe

Altitude: 3000-3400 feet

Temp:current 40-60F

The bike is running pretty well. It has a lot of power. No pop on decel when riding. When the bike is on the stand, I get the occasional pop on decel and the bike will hesitate when I blip the throttle, but only when the bike has idled for a minute. Otherwise, I can snap it with no hesitation. I figured I would put all this info out there because it might add some clues to whatever is troubling someone else.

Model: 2006 YZ450f

Edit Revision:edited may 15th from April 9


Main Jet: 170...changed back to 165

Pilot Jet:48(stock is 42)...kept it at 48 after trying a 45

Starter Jet: stock

Leak: stock

Fuel screw: scotts t-handle, 2 1/2 turns out

Needle: #5 clip (I richer from stock) stock needle...back to 4th(stock)

Air box: stock filter, no toil

Pipe/muffler: FMF Q2,was terrible, took away from the midrange,back to stock

Altitude: 4000ft-5000ft

Temp:current 10-15 degrees celcius...15-25 celcius

Humidity: dry 30%

Had to go back to almost stock, except for my pilot at 48, it still likes the fat pilot. I tryed the 45 and the bike ran worse(popping and hesitations). I think I will try one more clip leaner on the needle though, the mid range is a little out. I have noticed the bike hates filter skins, especially if they are over oily or dirty. I think the filter and it's condition is playing a huge role in the jetting for this bike, I am going to try a K&N.

on a 06 YZF450 with WB AlumPro 2 pipe. - was using 48pj / 170mj works great up to 80/85 degrees

swapped out to a 165mj for temps at/above 90 and it was flawless - I will try 168 next weekend.

Guess what.....no popping period! :excuseme:

Model: 2006 YZ450FV

Main Jet: 165 (168 winter)

Pilot Jet: 45 (changed from 42)

Fuel screw: Zyp Ty 1 3/4 turns out (varies w/conditions)

Needle: #4 clip ( stock NFPR)

Air box: Stock, Twin Air filters oiled w/Maxima FFT

Pipe/muffler: DRD Full SS System (no change to jetting when pipe changed from stock)

Altitude: 3500 feet and under

Temp:nominal 60-95F

Humidity: 30-80%

Both '06's using the same settings. Bikes run cleanly. Had an excessive amount of decel backfire when delivered with the 42 pilot, but no more. The engine can be made to stumble off idle on the stand, but it never shows up while riding, and it's a lot better in that regard than with the 42. Starts easy, too, even when dropped.

Model: 2006 YZ450f

Main Jet: 168

Pilot Jet:45

Fuel screw: 1 1/2 - 1 3/4 turns out

Needle: Stock Yamaha NFPR at #4 clip

Air box: Uni Filter and White Bros

Pipe/muffler: White Bros Aluminum Pro

Altitude: 300-1500 feet

Temp:current 70-100F

I gotta say... the bike has great response once fired. But for some reason I'm having problems starting it.

Any ideas?

Here is where I ended up:

48 Pilot

2.25 out on fuel screw

NFLR needle 4th slot

165 main, thinking I need to go to a 168

I have powernow plus's in front and back of the carburetor

2 stroke 250 filter cage

DMC pipe

:devil: 06 Yz 450......no popping and WFO fast. Main 162 or 165

depends on ambient temp. needle set at #3 with a 5 thousands shim under it. pilot 45 air screw..... warm the bike up and fine tune it til the dam thing idles smooth and happy. fuel!!!!! mix 1 part (that would be a gallon) 108 or 110 vp to 1 part super unleaded. cheap horse power boyzzz. No screen in the air cage and stock pipe. Popping is cured. Spark plug is light colored with a film of hazy brown. stick to the 165 if you have it still. Remember cold air is go air and hot air is slow air. lol.

07 YZ jetting

45 PJ Power nows, Wired Accellerator pump, Disconnected TPS.

NFLR - 4

165 main

Thanks I want to say the main is 165 and the I know the pilot is a 45 vs. the 06 42. I haven't checked the needle pos yet.


Stock 2007 jetting is:

160 main

45 pilot

NFLR needle in position 4.

BTW - I"m in Socal riding 1,000 to 4,000 ft mx.

YZ450 is hard to start (compared to crf450) and stalls in slow corners too much.

I'm going to bump the pilot to 48 and go from there.

(love the bike otherwise!)

follow up: the #48 pilot jet helped to ease starting and reduce stalling in corners. Success! May try raising needle and/or going up on main just for fun, but basically feels good now.

My 07 YZ450 carb settings.

Model: 2007 YZ450f

Zip Ty Carb Mod

Main Jet: 168

Pilot Jet:48

Starter Jet: stock

Leak: n/a

Fuel screw: Zyp Ty 2 1/2 turns out

Needle: #3 clip ( stock)

Air box: Twin Air

Pipe/muffler: Stock PMB end cap.

Altitude: 2,550 feet

Temp:current 40-90F

I have a new '07 YZ450 just past break-in, stock pipe and airfilter

Altitide: 7500 FT

Temp: 50-75F

Main: 158 (stock was 160)

Pilot: 45 stock

Needle: stock

Check the plug after 1 to 2 hours of 2-track and it is very light in the center and dark around the outer rim. Runs great, some backfire on decel, no noticable flat spot.

2006 YZ450 Supermoto

Main Jet: 172

Pilot Jet: 48

Starter Jet: stock

Needle: Stock NFPR

Leak: 45

Air box: K&N Holes drilled in box

Pipe/muffler: Dr D full

Altitude: 400 feet

Temp: 15-25C

The bike has been ported and balanced crank with a high comp piston.

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