OK, here's my situation; I have waited to post something because there are so many articles with similar situations but I really need some of your input on this.The 96 speedster has a rebuilt starboard side engine and the port side I'm not sure about. The port side runs excellent though there is a slight bog at 4500 rpm(assuming carb cleaning time). The starboard side engine(rebuilt in '09) keeps eating plugs. After about 30 minutes of riding around, the plugs foul and look dark chocolate brown(dry). Put new plugs in and she runs like brand new again. Carbs are set to factory specs and fuel lines and filters have been replaced.
My ? is; is the plug color a symptom of a rich condition as it has been my experience that a white plug is lean and a black plug is rich? Could the oil pump be calibrated, set wrong and could the dark brown plugs actually be a lean condition with the oil building up on the plugs because there isn't enough fuel to burn the mixture? Could they have set the timing too retarded. Funny thing is, with the fresh plugs the engine is incredibly crisp thru the entire rpm range.
I will be doing a compression check this a.m. and will be posting a picture of the plugs. Thanks for any insight you can give.
My ? is; is the plug color a symptom of a rich condition as it has been my experience that a white plug is lean and a black plug is rich? Could the oil pump be calibrated, set wrong and could the dark brown plugs actually be a lean condition with the oil building up on the plugs because there isn't enough fuel to burn the mixture? Could they have set the timing too retarded. Funny thing is, with the fresh plugs the engine is incredibly crisp thru the entire rpm range.
I will be doing a compression check this a.m. and will be posting a picture of the plugs. Thanks for any insight you can give.
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