..itsa simple setup that worked great, with one holdup...
..i had a 3/4" npt, free-flow brass muffler, inline of the induction tube, serving as an air filter...
..the cooling fan inducts a lot of "trash"...
..i had difficulty maintaining consistant air-flow, due to the muffler clogging...
..with it installed, and the carb tuned to it, my scoot performed as best as it ever has...
..and i still had the oem exhaust..
..air-flow increases as engine/fan speed increases, as fuel intake increases...
..it was not very difficult to tune...until the airflow began to decrease due to the muffler getting dirty...