The top speed of the motorcycle is what, about 50 mph? So if you gear it to a new top speed of 100 mph your acceleration will be much worse. Add in the additional weight and it will probably be a real dog off the line. Also, first gear is going to be
way too tall, so you will probably be slipping the clutch a
lot. You might want to throw some kevlar clutch plates in there when you have the engine apart for the hopup so that you don't keep frying the clutch.
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