More on quiet

[kerf]

Well, I'll state what I know. Many may not like the look of my expansion chamber and it did require a little effort to build but it works. My big issue with it is, while coasting over 20 mph, I can't tell if my engine is running. Wind noise completely drowns out the engine, it has stalled before and I only found out when I got on the throttle. As this is my only problem, I consider the project a success.

 

[Hive]

Muffler

Kerf,

I think your idea and what you produced is marvelous. I also amended my previous comments to include the need for bigger device, like yours.

Yes, I looked long and hard at your muffler and thought to take one of my old propane tanks and do the airplane interior thingy, but when I set it up along the bike, I decided it was going to look awful...on my bike. It is just the way the motor is set up, and the exhaust exit placement etc.

I was going to go so far as to remove the stock muffler and replace with a new flange at the engine cylinder, attach to propane tank muffler body and run it down down along rack stand, but decided, for now, to try smaller. It just did not work.

You need to quiet a few more ccs than my little and if it works for your bigger 20cycle, it certainly should work for a smaller engine.

I have a pic of your creation in my bike folder.

 

[Hive]

Muffler

Just in case this thing gets the best of me, because your ingenious muffler design has great merit, I have three questions.

1. Figuring you remove the baffle tube from the rear, how did you connect it to the intake area or does it hang free inside the chamber?

2. Can you list the fittings individually?

3. Pitfalls?

 

[kerf]

The muffler is about 13" long, just seemed about right. The outer jacket is a chromed brass 1 1/4" drain pipe, the end bells are 1" male x 1/2" female steel pipe fittings. The inlet is a 1/2" copper street elbow and the outlet is a 1/2" sweat x 1/2" pipe copper fitting. The end bells are drilled and tapped for #6 x 32 screws to hold them in place.

Start by turning the threads off the 1" pipe fittings, until they will fit snuggly inside the 1 1/4" tube. The inlet must have the threads ground off on the inside of the 1/2" fitting to allow the street elbow to fit inside. This joint is brazed with a bronze rod, use black iron fittings or remove all galvanizing before brazing.

The baffle tube is 1/2" EMT conduit drilled with 3/16" holes and it just rides inside the end bells. You could make this part from wire mesh, rolled into a tube if you wish. The fiberglass is un-backed pipe insulation.

 

[Hive]

Muffler

Are you referring to the chrome glass pack version or the larger muffler made from the O2 bottle? It seems the former.

I was looking hard at the O2 bottle version and how you connected the interior.

And, grateful thanks.

 

[kerf]

Oh dang. The O2 muffler used a 1/2" copper union. The nut is brazed to the end of the tank with nickel silver, the male threaded fitting is reamed to allow a 1/2" copper tube (I wound up using 1/2" EMT) to slide through. The baffle tube is about 7" long, closed on the end and bored with 3/16" holes. This is then brazed into the male fitting. The design allows the baffle to be removed for cleaning. Note oil drain plug in the tank.

 

[kerf]

Sorry, didn't mean to submit.

 

[Hive]

Muffler

Ingenious! Thanks.

 

[duivendyk]

There appear to be two different muffler designs around,the O2 bottle and the drainpipe affair,has this one superceded the O2 version?
I crafted a muffler using a drainpipe for my TLE 43,it has an L configuration,the down pipe has an elbow on it connecting to the horizontal portion.Instead of rolled up wire mesh it uses spiral wound steel wire,with fiberglass roving wrapped around it.The overall lenght is about 20" (10+10)
.I found a 1 1/2 " conical chrome plated pipe shroud at Lowes that could be reworked as the end piece to connect to the engine's exhaust outlet via an elbow and with a hose clamp to the down leg of the muffler.
The whole contraption is held together with hose clamps.It does an adequate job as a muffler and is easy to build (no brazing or metal working is required) and takes only minutes to take apart.The wire spirals and fiberglass are also easy to make and replace if things get crudded up inside.My camera has been on the blink.When I get it fixed I will post some pics.

 

[kerf]

Yes, the O2 version superseded the glass pack version. The glass pack had better top end the O2 has better bottom end and is quieter. One must remember that my engine, with the stock muffler only, had all the charisma of a chain saw.