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1997 KTM 250 EXC Jetting

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Hello all,

I have a 1997 KTM 250 EXC that I believe needs jetted. Below is the info for my riding and the bike. 

Carb: Keihin PWK 38

Main Jet: 175

Pilot Jet: 45

Needle and Position: Unsure of how to check that.

Air Screw: 1.5

Altitude: 700-2000ft above sea level

Temperature: 60-90 degrees fahrenheit

Style: Tight Single Track, All throttle ranges, but do lug quite a bit as I ride with slower riders

Plug: BR8EIX (Just Replaced)

Premix: Maxima Super M at 45:1

Fresh Air Filter

Fresh Exhaust Packing

Float Height Set According to Manual

The bike has a ton of splooge coming from the exhaust, as well as having trouble idling both with and without load. It has also been fouling plugs. 

I did some research and found a chart for a 1999 250 EXC and it says to do a 178 Main, 45 Pilot, N85C in position 2 with the Air screw 1.25 turns out, but the 178 Main sounds like it would make it worse.


Thank you in advance to anybody who helps!


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