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Advice - 03 vs 04 YZF250 throttle response

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Hey Everyone - any good advice appreciated. My brother and i both ride mostly woods and some motocross. I love the YZF250 because it is sooooo versatile. My brother has an 03 YZF250 with all stock jetting and a power-now. After 24 years on 2-strokes, i bought my 04 YZF250 this winter. However, my 04 is not as crisp or smooth as the 03. It just "feels" more subdued and "rougher" in response. I have the power-now also. I have the dr. d pilot air screw and have adjusted it many times. I've tried to richen the needle and it felt worse so i went back to stock clip position. Recently I threw in the 40 leak jet and it feels somewhat better but still not "crisp". Compared to the 03, I get more pops on decel (although with pilot air screw adjustment it can be minimized). What baffles me is nothing has been touched on the 03 jetting wise, yet my 04 just doesn't feel as strong or smooth with throttle response. Since we ride together we can switch bikes and compare. Everytime I get on the 03 it just feels "crisper, smoother and stonger". Valve clearance on both bikes is in spec. We ride in Missouri (roughly 1500 feet altitude). Any ideas on why my 04 seems to run worse than the 03???

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Go up one on the pilot jet and drop the needle two positions. Mine was the same way.

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I know it seems like it's the wrong thing to do, but if you go two clips you get results one way or the other. If it's worse go two the other way. My 04 250 ran bad from the factory so I played around and it ran great before I sold it. I think I also ended up buying the JD jut, but I kept all the positions the same. Never changed the main. At least during the summer.

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Dropping the needle leans it out correct?

Trick question.

Needles are numbered from 1 to 7 or so. Clip position 1 would be at the top of the needle 7 would be towards the bottom or point. So "dropping" could mean three things. 1 "Dropping the number" relating to the respective clip position numbering system or 2 "Dropping the position" relating to the needle's top and bottom or 3 "Dropping the Needle" would mean moving the clip up so the needle moves down or vice versa.

Now I may shove my foot in my mouth, but I believe he was telling you to drop the position in relation to top and bottom, NOT lower the number. Normal is position 4, try clip position 5 or 6.

Moving the clip up to a lower number "Leans" Example: position #1

Moving the clip down to a higher number "Richens" Example: position #7

Hope this helps,

Shane

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