99-01 KX250 riders, any idea what size pilot jet you have?

I'm trying to get rid of the spooge and am doing some re-jetting.

I have the JD jetting kit and contacted James Dean and he said to try dropping my pilot jet size to a #40. I'm running a #45 right now.

I was hoping to see what you guys are running on your bikes so I could get a baseline.

Also, I haven't ordered jets in while and I know that guys like Jay, Jason, Ed, Chokey, Art, and a few others routinely get your jets from known places. Where would you suggest I get one. My local dealers are a shot in the dark so I'll probably just order it online and pay shipping.


I have a box of jets that I collected over the years. We used to have a good Kawasaki parts person here that had and would get you any jet you wanted. Most of the time I run a 45 or 42 pilot jet, a 40 though is not out of the question. I have a friend that runs a 35 but I have not had the need to go lower that a 40. Good luck with this Karl.


My jetting may not be relevant to you, as I live at sea level and it's rarely cold or dry here. But my pilot runs between a 45 and a 52, depending on the weather. Lately the 50 has been perfect, if not borderline lean on those chilly mornings. In the middle of the summer the 45 is just a tad rich but a 42 is usually too lean and tends to make the bike run-on when I let off the throttle for turns.

I ride a completely stock '02, except for Boyesen Carbon Pro reeds.

Thanks guys. I forgot to give you the background. VForce 3 reeds, Gnarly pipe, "Q" silencer, no porting or other engine mods. I'm at 600 ft above sea level and dry conditions, humidity typically less than 30-40%, temps around 60-75 degrees.

Will the VF3 reeds typically cause you to drop a size in jetting?


The Gnarly pipe will certainly require jetting changes. The V-Force typically doesn't.

So, any suggestions where I can get a #40 and probably #42 pilot jet online?


Thanks KX02. I just read your post and I'd forgotten about these guys........ http://www.motorcyclecarbs.com/index.cfm

They're not cheap but I've used them before and they're reliable.


UPDATE: I decided to check my local Kawi/Honda shop and they were closed today and will be til Monday or Tuesday.

So, I went to my local Yamaha/Suzuki shop and lo and behold they had the #40 but not the 42. So, I put it in. Starts fine but I need to choke it a little more than I used to. I adjusted the air screw somewhat but I'll need to get it on the trails to really dial it in.


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