Question about Harley Davidson XL 1200 C Sportster Custom Motorcycles

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Mmi have a 99 1200 sportster xl runs really rough like not on all cylinders not sure about kind of carb but its stock with bike and black smoke coming out of front cylinder and plug is black like carbon buildup inb frt cylinder

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If it's the stock carb, it is a Keihin CV carb. If you've got black smoke coming out of the front cylinder, this means it's running very rich and especially on the front carb. I'd take the carb off and go completely through it cleaning and rebuilding it. I'd also replace the intake seal where the carb plugs into the intake and the intake seals where the intake meets the heads. It sounds like your carb is flooding. Unless you are familiar with these carbs, I'd advise you to take it to an experienced mechanic. These carbs are complicated and not meant for the amateur to be rebuilding them.

Good Luck

Posted on Mar 18, 2011


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