Sometimes you will get some fuel out of the exhaust. Most of it is the oil that is blended into the fuel. The motor could be running too rich. You can lean out the carb high end needle, turn it clockwise a little at a time, like marks on a clock. It is easy to go too far and get the carb out of adjustment. Do one "hour" at a time. You want a nice plume of blue smoke to come out of the exhaust when you accelerate. Most nitro engines like to run around 210-240 degrees. You do not want it to go much over 240 degrees or it can overheat and be damaged.
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Sometimes you will get some fuel out of the exhaust. Most of it is the oil that is blended into the fuel. The motor could be running too rich. You can lean out the carb high end needle, turn it clockwise a little at a time, like marks on a clock. It is easy to go too far and get the carb out of adjustment. Do one "hour" at a time. You want a nice plume of blue smoke to come out of the exhaust when you accelerate. Most nitro engines like to run around 210-240 degrees. You do not want it to go much over 240 degrees or it can overheat and be damaged.