07 WR250 jetting

I just got this bike and need some suggestions on what jets i should put in. the bike is completely stock and I am going to do all of these mods to it before i work on the carb: remove air box snorkels, Twin air powerflow kit (doesnt really increase air flow), GYTR 96db exhaust insert (flows a little better than just removing the small pipe, spark arrestor still in), remove AIS, and cut the gray wire. so basically all the free mods, and i will also put the YZ throttle stop in and do the AP mods.

I am in san diego and will be riding this bike in the so cal desert for the season, so the temps are hot like 80-100 deg. and the elevation 0-500 feet.

I am also wondering what needle i should use. i have the JD jet kit needles for an 04 wr250, so if this works what positon should i put the JD (blue) needle at? thanks

I think JD recommends the red needle for lower altitude and higher temperatures. I have seen some people using the blue needle. If you use the red, it should be 3rd from the top. That's the one I used with the JD 80 main with the mods you are doing (I have an '08 WR). I moved the clip to 4th from the top when I put an aftermarket pipe on it and left the jets the same.

ok i just ordered an 08 yz250f exhaust (stock muffler) for this bike. what would you recommend i jet this bike to with the exhaust?

What exactly are you running

main-

pilot-

leak-

air-

Yamaha sells an AIS removal kit that comes with the jets you will need, its cheap and it works, actually for all WR's.

I highly recommend it.

Ed

Right now the bike has stock jetting, and i dont know what that is. i already installed the ais removal kit and have done the rest of the free mods. i have a good selection of jets, but since im not an expert i cant really just guess what it should be jetted to. with the yz exhaust and air box snorkels removed, what do you guys think i should jet this bike to? i ride in the so cal desert

What did you end up going with for jets? I also will be running the yz exhaust on my 07 WR. I used the recommended settings in the JD kit: #180 main, stock pilot, #40 leak jet, RED needle with clip 3rd notch down, and the THIN O-ring mod. I also am in the 0 - 500 elevation range, and have the snorkel removed.

The low end bog is gone now but the bike still seams very slow. I'm coming from a Suzuki Z400 and this bike is a dog compared to the z400. Acceleration is slow and I'm topping out at about 55mph.

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