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Jetting 2002 WR250 - Pilot Jet?

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I know this belongs in the "jetting" forum but thought would get more 2T Husky exposure here.

Problem is 2002 WR250 is running rich (what else is new:crazy: !) from when got this bike a few months ago. Went from the stock 35 pilot to a 30 and now to a 25 and still rich! I am 3 turns out and will run fairly well when choke is turned off just after start, indicating rich. Slide is a 4.0, I believe, not sure what main jet is but suspect stock 400. No apparent leaks as everthing tightened up and WD-40 leak check ok. Do not believe needs a top end as bike was not run much by previous owner.

I am afraid to go down a 20 or 15 pilot, but should I?

What else to do? The only last thing to do is run 40:1 from 50:1 on initial runs. This is not drastic enough to severly lean it is it? There is something else going on....help!

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Thanks Bob....some good info searching now. Damn....this may be it but I don't blow alot of smoke and the oil level does not appear to deplete after ride.

What about float adjustment?

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Did the float adjustment today...they were way off!...runs a ton better was way off and bike would leak when on kickstand. So appears to be this and not the crank seal. This appears to be the issue. I adjusted the tab on the float so now the floats are level and about 14mm from base of carb. Anyone know the spec on this for the TMX 38?

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I have the same problem with my 01 wr 250. I was told to try the JD jetting kit(01-05 honda cr). I guess this carb (mikuni tmx) is a pain in the a$$ to get the jetting right on it.

I guess I will check the floats when I rejet the carb

Mike

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I have the same situation with my 250...I suspected the floats but could not get a spec for float height.

Let me know if you get one, okay?

That 14mm measurement how exactly did you do that?

-Thanks

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I have the same situation with my 250...I suspected the floats but could not get a spec for float height.

Let me know if you get one, okay?

That 14mm measurement how exactly did you do that?

-Thanks

Reading some of the carb websites, said to measure from base of carb (float cover off) and measured from float cover base (the aluminum base of cover removed) to the top of the float. The mistake I made is I think should be measure with carb on side or at 45 deg angle. I did it totally upside down. The floats did become level upside down after I bent the tab down, so think ok.

Did not want to go too much. Will see how it runs with this. Seemed to at least stop the leak.

At the same time changed main to 390 (was bogging at full throttle). I changed the pilot from the stock 35 to 25. Seems to start decent.

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Reading some of the carb websites, said to measure from base of carb (float cover off) and measured from float cover base (the aluminum base of cover removed) to the top of the float. The mistake I made is I think should be measure with carb on side or at 45 deg angle. I did it totally upside down. The floats did become level upside down after I bent the tab down, so think ok.

Did not want to go too much. Will see how it runs with this. Seemed to at least stop the leak.

At the same time changed main to 390 (was bogging at full throttle). I changed the pilot from the stock 35 to 25. Seems to start decent.

I know exactly what you are saying...my floats are a little higher than yours.

Usually one measures the float with the tang just touching the needle.

Let me know it works out for you.

Thanks

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Float measurement should be made with the tang on the needle(in this case with carb upside down).

I switched mine to 380 main and left the stock 35 pilot. Went 2 1/2 turns out on the idle screw and mixed gas 40:1. Runs alot better. Oh, I did readjust my float level also. It was way off too.

Mike:ride:

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I have the 35 pilot and went back to the 61 needle and my 07 is still running rich has anybody tried the 4.0 slide my bike has a 3.0 now ?

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I have the 35 pilot and went back to the 61 needle and my 07 is still running rich has anybody tried the 4.0 slide my bike has a 3.0 now ?

The 4.0 slide is leaner and will help clean up the idle.

I think the 250 runs a 4.0 stock the 125 runs the 3.0 as far as I can tell.

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My manual says 4.0 but it is ether a 3 or a 3.5(?) in my bike, i'm also going to check the float as fuel does seem to come out of the over flow hose pretty easy

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mine has a 3 slide as well seems to running rich tried a 30 pilot didnt seem any better droped the needle one clip not good at all not shure what to try next.

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I think it's the the slide, i'm going to change it to a 4.0 and check my float.

I've tried changing the needle back to the 61 and no difference, so back to the

60 and check my float for now.

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I think it's the the slide, i'm going to change it to a 4.0 and check my float.

I've tried changing the needle back to the 61 and no difference, so back to the

60 and check my float for now.

Let me know what happens...I have the same issue and am running a 25 pilot with okay results

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I hade same problem, changed slide from 3# to 4# made a big differens

I´m now running 30pilot, 60needle, 4#slide, 2.5trns on airscrew and 410main to smooth out top end power

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Is the float suppose to be 14mm....now I am not sure if this is the correct value? Still rich.... I think I have to measure at 45 degrees just before seat needle contact.

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