Homemade Silencer

[sectionone]

I've started a project of making my Fantic Section as quiet as possible for backyard riding. I've had no complaints yet and want to keep it that way! Here is my first effort:

It's made out of a silicone baking pan folded in half, with rivets and stationary binder clips holding the fiberglass and perforated aluminum tube that I made from a sheet. If you've heard of the dB Snorkel, it works in a similar way but at half the weight. Mine weighs less than a pound. I need to work on the mounting system since my velcro and wire mounting falls off. When it does fall off, I immedietely can tell the difference as the silencer works quite well! The whirring of the powervalve is a lot more noticeable. When in action, it pulses like a frog's throat. Since it's soft and floppy, rear suspension isn't affected but as you can see it's tweaking the fender. Some sort of reinforcement is in order. I found out that they make these silicone pans and sheets in black so I'm going to pick some up today.

Excessive dirtbike noise is an issue that plagues the sport and I've been researching what other dirtbike racers are doing to their bikes to make them quieter and some other methods are wrapping the header pipe and adding sound padding on the skidplate. Baking silicone sheets can withstand 500 degrees farenheit so I'm going to test some strips on the header pipe and maybe the cylinder. Any other ideas?

[gizza5]

Any other ideas?

No I don't think so, you seem to be doing fine without us

[hughesy]

I thought April 1st was almost 2 months away.

[chris morris]

Bet the wife's gonna be well p****d off when she realises you've ruined her best pink handbag.

Edited February 6, 2007 by Chris Morris

[andy m]

You are obviously having a laugh right. Too much obviously.

[bilco]

I see something like that down at ann summer's the other day.

[feetupfun]

Why does it have to be silicone? What's wrong with aluminium? You could support it from the existing muffler if you make it light enough.

[mattp]

Hi.sectionone.

You better get a patent out on this one before the works boys get hold of your idea.

Are you looking for investors?

No i dont drink a lot ! F******* spill most of it.

[sectionone]

I have a new design. It's called the PabstGas model!

[jimsshed]

I tried a similar concept on my son's Beta Rev-50. They're awfully tinny and loud (bad Beta Motor Co.).

I got a roll of 50mm exhaust header-wrap and tightly wrapped it around the expansion chamber from where the header pipe is welded onto the expansion chamber, right back to just behing the chamber's mounting bold. I secured it at each end using strong zip ties.

The noise reduction was enormous and he could comfortably ride around the back yard, and the header wrap was surprisingly durable. It never fell off or became loose at all. Even the pressure cleaner didn't budge it.

FYI: Exhaust header wrap is a soft woven fibreglass fabric ribbon used on drag cars etc to shield parts in engine bays from high radiated exhaust temperatures. You buy it from performance auto stores.

Jim

[sectionone]

I heard that header wrap was used on race cars to keep the exhaust gases hotter so the engine has more power. This also caused the pipes to become brittle and crack. I won't have this problem riding in my backyard since I tried wrapping a strip of silicone baking sheet on the header and it didn't melt. This means it didn't get above 500 degrees F. I'll try wrapping more but what I think what would help silence more is repacking the middle muffler. It's double walled but not repackable so I'll have to make doors on both sides.