Yes and no.
A stock can is very quiet.The prop makes more noise than the engine at half throttle.
A gutted can is loud, but not as ear peircing as a gutted can on a two stroke but still annoying.
The header/4hp briggs muffler combo I use falls in between.Loud but not enough to be a noise issue.

An open header is as bad as an unmuffled tuned pipe on a zen.

Hey Bob
I have a MHZ Gearbox (1 in & 2 out --- +19% out) -- would one of these Honda drive that puppy ?

Where can I find one ? Always been a Honda guy ..

Thanks - Cool Project

Randy

I messed with over drives for a while. the end result was I went faster using direct drive, there is too much torque loss going through the OD.With 2 out its even worse.

Someone asked me about this project the other day.Its kind of stalled.This boat is not light enough, it weighs almost 7 lbs bare.

Over the winter I'm going to see if i can get a AC Rebel.