Drat!. you asked this before I've even started!!! Because Of all the flats I've gotten to de-commission my ride, I'm concentrating elsewhere.
But next up is an intake muffler. I'm thinking similar dimensions as an exhaust muffler, only on the intake. Similar center tube, drilled and crimped, in the middle enclosed within a can.....with a large, nearly 2 inch hose to conect to the existing carb......
Drat..... I wish my ride was rideable so I could work with the noise!!!
Hmm....You could always stick another piece of filter in there. On mine I hardly hear the intake with the factory setup. My brothers frame is too small and there is no intake on his...just a mesh screen with glue lol.