Why are you pushing this viewpoint? It makes your engine much louder and probably run worse. Don’t start multiple threads to give bad advice-Run the dam thing with a Straight Pipe. BIG difference....YW
It's no louder then a lawn mower. You should hear what passes this house.
I'm Tame ~
I built this Zeda PK100 on a Diamondback Outlook and it was okay with stock muffler, but I took a handle from a fetrilzer lawn spreader and cut it, took a old stock muffler and cut off the muffler itself and welded the tube to the pipe, and at the end put a plain 6" tubular lawnmower muffler on it. It's a little louder, but this baby went from 37mph to 51 mph with a little adjusting richer of the needle clip due to backpressure change. Well worth the time and if you don't weld, just drill through both pipes and run a bolt through there and that'll work also. Much improved everything power wise and I go by so fast the neighbors think I'm a jet...
it has a lot of bucking and lurching at low rpm, kida like a hotrod with a real radical cam in it, but once you give it just a little gas it smooth right out and is almost like a 4 stroke until you hit the powerband. Mine seems to get a second wind from 7/8 throttle to WOT, and seems like the rpms almost double at the end. The difference in low end torque, mid range acceleration and WOT top end belies the fact it is only increased 13cc, and is almost double the performance improvement from a 49cc(really a 37cc) to a 80cc(really a 66cc) as this ones total displacement measured in US standards is 79.54cc. The compression is up as if your not going about 10mph or faster even with new tires it just skids the rear wheel. I live by a steep decline so I usually just get going about 12and then it breaks compression enough to turn over and usually 1-3 revolutions and its running.