Hello Jerryls

I also live in Las Vegas and ride an 03 wr 450 my only jetting changes are a 160 main 162 seemed to fat and the fuel screw.I feel that the fuel screww (Zip tye) p-38 is the best thing since cold beer. I was told you can range 2 pilot sizes by adjusting the fuel screw. I have not toched my pilot or needle and my bike frickin rips.

Plaz Conner in Las Vegas

Grey wire,throttle stop, spark plug, air box, fmf pipe, 160mj, pro taper, uni filter, hand guards p-38 fuel screw/ap cover.

Hey Plaz,

I used to think my bike ripped, until I cut big ol' holes in both sides of the airbox (it won't rain again until next spring), removed the screen in the airfilter, added the PowerNow, and put in the PMB insert. After doing this, I had to move up to 168-170 MJ (depending on temp). Now it rips. Highly recommend it. If you're willing to cut up the airbox, I can give you details for the $7.99 "Home Depot filtered shower drain assembly" (patent pending). Sounds stupid, but it's actually quite effective at both increasing airflow and filtering dust, and looks half-way professional (if you're a half-ass professional like myself).

I see you have a FMF pipe on there. Do you have a silencer or something choking it up? I would think you'd have to jet a bit richer with that.

Tried a 160 & 165 MJ last week, and the engine was extremely lean. Are you running the JD kit?

Also tried a 50 PJ, but it was really hard to start. Still having some issues with the low end bog. Waiting to hear some feedback on a #40 leak jet. Anyone?

Where do you ride at? Do any of the MRAN races?



40 leak jet will get rid of you bog! Careful with a real small pilot on the 03/04 WR's they really soften the bottom end just off idle. I dont recommend changing the pilot below a 42 for this bike. 48/45/42 seem to be the ones that work for all conditions. I used a 45 pilot at 10,000 feet and 80 degree weather in Colorado. Worked very well. :)

Hi Jerry:

I agree with you on flowing more air the only thing I have done to that system is remove the snorkle and replace the stock element for a uni.My pipe is a power core four w/spark arrestor screen and stainless power bomb header.

I live on the west side Spring Mountain Fort Apache area, I do my short rides at the Bird Springs, Cotton wood area ride towards jean and good springs.I like Nelson Hills & Beer Bottle Pass.

I have not done a race yet this is my first dirt bike since I was a kid some 18 years ago. Anyway I have been racing moutain bikes and road bikes for 8 or so years.

Keep in touch


I'm in the same boat. Gave up dirt bikes when I started riding crotch rockets (way back in '87). And gave up the crotch rockets last year when my daughter arrived. So I'm relearning the whole thing too. Of course the suspension on my WR is a little better than my '76 CR250


We'll have to go riding someday. I really want to see how much of a difference that pipe makes. I'm booked up for the next couple months (accountant = busy season). But it would be a nice change to have someone to ride with. Not much fun having all these spectacular crashes with no one there to see it.

Try out some of the MRAN races. I've learned more in three races than in all of my play riding. And I need to recruit more people in hopes of finding someone I can keep up with.



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