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JD Jetting Kit 4 2 Stroke?

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anyone running a JD Jetting Kit in their YZ250 2 Stroke? I stumbled across one for my YZ. Got it form a riding buddy for a case of beer. When i started to read the recomendations, i felt they were a little lean compared to what i was currently running.. I am running now a 48 pilot 178 main and needle in the 2nd postion. the jd kit says 45 pilot, 172 main and their custom needle in the 3rd position. I am going to try their recomendations, but i was curious to what others thought.. I live in Las Vegas, run 36:1 redline, 100 octane pump gas, and ride in 100 degrees. I have had no carb issues, no spooge nuttin! when i look at my plug, it looks perfect with my current jetting. If the JD kit could make me feel like a big boy, then i will stick with it..

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Remember that JD's kits have entirely different needles, so it's hard to compare to the oem setup. I've used his stuff on 4 strokes with great success. You can email him directly (check his site for the address) and give him your particulars and he will give you a good baseline. One thing, I know is his company tests everything they sell in a myriad of conditions.

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I don't know about the JD kit, but the jets and octane that you are using worked great in my 250. I just had Pro circuit do the head and cylinder. Other changes are 180 main, V force 3, and pro circuit pipe, with the stock silencer. The power from my 250 is KILLER! I have to run over 101 Oct now, but it is worth it.

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I have the jd kit in my 06 yz 250. His specs are right on the money. Obviously a person has to adjust some for temp and altitude.

I am using the red needle in position number two with a 168 main. The kit is nice. On my bike it made the midrange pinging go away without having to use race gas. Throttle response was improved (like the bike needed that). The power starts at a lower rpm. The sudden hit is spread out some.

One of our memebers sent me a great jetting chart for my bike. after looking at this chart it is almost worthless to recommend a "perfect" jet for anyone.

My altitude, temperature, and the urine we get for gasoline here in utah calls for a main jet two or three sizes leaner than a person in california would need.

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I use the needles in the kit and I like it. But i cant use the jets in the kit, they are too lean for me here in Hawaiil.

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I have the jd kit in my 06 yz 250. His specs are right on the money. Obviously a person has to adjust some for temp and altitude.

I am using the red needle in position number two with a 168 main. The kit is nice. On my bike it made the midrange pinging go away without having to use race gas. Throttle response was improved (like the bike needed that). The power starts at a lower rpm. The sudden hit is spread out some.

One of our memebers sent me a great jetting chart for my bike. after looking at this chart it is almost worthless to recommend a "perfect" jet for anyone.

My altitude, temperature, and the urine we get for gasoline here in utah calls for a main jet two or three sizes leaner than a person in california would need.

so is it possible to get rid of the necessity of race gas by using the jet kit? That would be really awesome

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One of our memebers sent me a great jetting chart for my bike. after looking at this chart it is almost worthless to recommend a "perfect" jet for anyone

I would love to see this chart

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I was able to use the jd kit and not need race gas. Then again, I did not need race gas using the optional needle Yamaha sent with the bike...The N3EW.

If my bike is rich enough to not need the race gas, however, I felt like some respose was lost. Not a lot, but a slight amount.

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