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Help with Pilot jet on 2007 YZ 85

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I'm having trouble on finding spefic info on pilot jet for the 2007 yz85.... Bought one that was used at sea level, problem is we are at 4100 above sea level here. Bogs on inital throttle input then runs wild...very strong... .Was thinking that we need more air and less fuel.....Took the car apart and cleaned everything, (will be taking it down again to check the float level)... any suggestions on what pilot jet to run if the floats are not the problem?.... Also it was unclear to me(a 2stroke newbie) if turning out the air screw was providing more air (what i think) or less air?

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Not much a clue about yz85s but you are right at turning out the pilot screw lets in more air. In Generel IMO at sealevel the jets get bigger and slim down the warmer it gets. The higher you are they grow smaller and get even smaller when the temp climbs.

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So pulled the pilot jet out, it was a 42 not the stock 45, so went ahead and put in a 40. has virtually done away the the lagg/bogg.... air screw is at one turn out, haven't really fine tuned it yet.

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Have you cleaned and repacked the silencer? That can be a very common cause of rich jetting at low rpms type symptoms.

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I live at 4600 ft--seems like I went down at least a couple of sizes on the pilot and a couple on the main on my son's YZ85--also dropped the needle--ran much better. These bikes come very rich from the factory and also use a richer slide versus the other mfrs..

The hot trick is to use the KX85 slide and needle to lessen the hit and smooth the power band--some good threads on this--just do a search.

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