I want to cheat!

Ok. Here is my problem. I have a big trip planned for this weekend and am almost done with the complete rebuild of my 2003 WR450. I just fired it up for the first time in over two years. I need help with the Jetting and was hoping to find someone else with the same setup as I have and just "copy" there jetting. Because I will not have much time at all to "test and tune". So here is my set up, I have the JD jet kit and installed according to there instructions (cant remember which needle but I think its the 168 jet). I also have both powernow and powerplus valves installed, I have the quick shot and a brand new FMF 4.1 full system, I installed the zip-ty fuel screw and hot start nut, its got an iridium spark plug, installed the twin air system and modded the hell out of my air box.

I live in Colorado at an elevation of 5600 feet. Thanks for any help!!!

Check with JD directly.... James is pretty good about having all the info

INDY's jetting chart will get you real close. FYI, I have a YZ exhaust and unmodded airbox (snorkle removed) at sea level and run almost right on these settings, maybe one step leaner on the needle. I like the starter jet rich, so I leave that at #70 year round. I just re-jetted for current weather and it was just about perfect on the first try (sea level, 45-60, 170mj, 48pj, JD Blue #3)

Elevation 4,000 to 8,000 feet:

30 to 45 degrees: 170 main, JD Blue #4, 48 Pilot, 1.75 turns, 72 starter jet, #0 leak jet

45 to 60 degrees: 168 main, JD Blue #3, 48 Pilot, 1.5 turns, 70 starter jet, #40 leak jet

60 to 75 degrees: 165 main, JD Red #5, 48 Pilot, 1.25 turns, 68 starter jet, #40 leak jet

75 to 90 degrees: 165 main, JD Red #5, 45 Pilot, 2.0 turns, 65 starter jet, #50 leak jet

90 degrees plus: 160 main, JD Red #4, 45 Pilot, 1.75 turns, 65 starter jet, #60 leak jet

So if im starting and idling fine, then leave the pilot alone right? And if it flatlines twards the middle and top then its the needle right? And if it blows black smoke when I blip the throttle what would that be? :thumbsup:

I run a 168 main, JD blue #3, 48 pilot, Soldered closed leak jet, and 1.5 turns out on the fuel screw. I have opened up my air box and stock exhaust. No bog. The bike flat out rips.

Thanks! Anybody else from Colorado have any input?

And if it blows black smoke when I blip the throttle what would that be? :thumbsup:

That would be a rich condition, mabye mainjet?

Ya I figured it was rich but do I play with the Main jet or the needle?

By the way I forgot to thank you Rich for your input. This is what I need to know! Thanks again!!

Your getting a squirt of gas from the AP pump when you blip the throttle. I wouldn't worry about a little soot. How it preforms is more important to me. I have never fouled a plug. Make sure you warm it up with a good 15 to 20 min ride before you make a change. The only thing I would change form the jetting set up I gave you is a #40 leak jet for warmer weather

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now