turns out... i suspected right.
the first order of business, more power (that and a chrome-endectomy). thanks to british customs, I got a new ceramic coated header and sleeper exhaust system. we yanked out my old airbox and replaced it with a pair of big lung k&n filters. and since i can handle a little more juice, we rejetted the carbs with a 140 main jet and a 42 pilot jet. that's better.
now i sound all vintage-y like i should and I've got a few more ponies in the back pocket.