Motorcycle Repair: Misfire, downhill sections, hypercharger

Question
The plugs are generally black and sooty.
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The text above is a follow-up to ...

-----Question-----
Mike, I have a 1994 Dyna which is running like a bag of nails since the weather began to turn colder. My local garage tells me this is a problem with C.V. carbs and nothing short of changing the carb will help. This to me seems like another way of dipping into my pocket so if you can be of assistance I'd be very grateful. The bike is running the standard C.V. carb with Hypercharger and has been Dynojetted. The problem seems to be misfire and subsequent back-firing. I notice it seems to start on downhill sections. If there's anything else you need to know just e-mail me. Thanks,Kev.
-----Answer-----
Pull your plugs and let me know what color they are
Mike

Answer
Since your plugs are black and sooty you are running rich or bad spark. If you havent make any changes to the bike I would look at the spark. Do a OHMs test on the coil and plug wires. If the coil and plug wires are weak you will foul plugs
Good luck and happy riding
Mike