Quiet Performance Muffler

[NapaMike]

Hawaii is cracking down on loud, modified scooters. I usually install so called 100cc big bore kits and performance exhausts on my son's scooters. Is there a way to have the extra power while keeping the noise down? Can you run a stock muffler on a big bore and still have similar power? What's the solution to this problem? We would like to have the power to climb hills without bogging, while not attracting unwanted, expensive attention.

Any help appreciated

Mike

[Irish]

Do the police have anything to check the noise decibles with? That is the only way to check it. Someone cannot stand next to your scoot & say-That's too loud & give you a ticket for excessive noise. If they do you can have it thrown out in court. Irish
P.S. Court is a pain but if they pass laws they should have the equipment to enforce the laws. Be a "Pain in the ass" & fight for your rights!

[Roscoe]

I see some advertised but I have no idea how much they actually quiet things down, they seem to lower the pitch more than anything which might be enough. I've wondered how Honda generators can be so quiet. You can tune a muffler to certain frequencies to cancel out the noise but it's tough to do over the wide range of scooter engines. Google "acoustics, single cylinder engine" and you'll see what you're up against. I'd probably try a muffler from a 150cc engine (some welding my be required) and see if that does the trick.

[wheelbender6]

Try using a stock muffler and blue print it a bit. Use a Dremel tool to enlarge the opening at the cylinder.

[Irish]

To the BEST OF MY KNOWLEDGE the only way to increase power is to lower back pressure , thatmeans MORE noise! That's on racing motorcycles. I assume that it works the same but I'm no expert on scooters. Irish

P.S. I used to run straight pipes (with engine tuned to them) at the drag strip but there's NO noise police there!

[Shadowfire]

With a big bore kit, you need something that can flow the exhaust without excessive restriction AND has enough surface area to absorb the sound waves (change them into heat). You just need to do your research before purchasing the muffler. In order to effectively quiet up a higher flow rate, you basically need a bigger muffler section. If the performance muffler has a muffling section of similar volume to the stock muffler, its likely to be louder than the stock pipe.