Exhaust

Dave31

Moderator
Staff member
Mar 1, 2008
11,204
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Aztlán, Arizona
Please do not ride with your baffle off...we have enough groups here in Tucson that are trying to ban Motorized bicycle again.

Before Oct. 06..motorized Bicycle were illegal in the Sate of Arizona. A lot of people worked really hard and spent lots of money to pass HB 2794 to give YOU the right to ride your MB. Ridding around without your baffle is not helping the cause. :(
 

eDJ

Member
Jul 8, 2008
530
0
16
Wayne National Forest
I grew up in a school of motorcycling where people were told not to pull the baffles when they rode. It wasn't as much to do with the noise as it was with keeping oil on the cylinder walls. That little bit of back pressure was believed
to actually aid the lubrication of the engine and keep it from possibly incurring a cylinder wall/piston seizure. Todays better 2 cycle motor oils do a good job of
lubricating with the BIA/TCW standard, but who wants to overhaul the top end
just to have some noise.....which will be the principle gain of pulling he baffle.

And these Chinese cylinders don't have a steel sleeve in them like the Russian ones did. They have a hard chrome coating I understand that helps enable it to hold oil better as hard chrome is porus....but may not be so forgiving of a seizure. I've wondered if that's why some of the mufflers that come with them
were made such that they couldn't be taken apart.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
236
63
up north now
The baffle is a piece of sheet metal or some have a tube inside the muffle. The baffle serves to deaden or soften the exhaust pulse sound.

Removing or modifying the baffle increases sound and the sound becomes "sharper'' or more crackly.

If you remove the baffle, be sure to run a plug check and listen to the engine. Make any adjustments to your mixture that you need to. The engine will usually (always) run leaner with less baffle.
 

jezusjonz

New Member
Feb 26, 2008
192
0
0
Indiana
Or you can make a baffle ejector like this. Push the cable to open the baffle pull it back in to run quiet. Pictures show the cable (manual choke cable), attachment to muffler,baffle in, and baffle out. Sorry just something I dreamed up one day and has no pratical value......lol
 

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jasonh

New Member
Jun 23, 2008
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Longmont, CO
Hey that's actually pretty cool believe it or not.

I was thinking you could do dual exhausts with 2 different tuned pipes...one for lots of low end torque, and one for lots of high end hp. Then use a cable and some type of valve so you can control which one to use.
 

eggi96

New Member
Oct 5, 2008
6
0
0
Australia
so a baffle is a bit like a catalyser in a car exhaust it cleans out the fumes and makes the sound softer am i right
 

Dan

Staff
Staff member
May 25, 2008
12,775
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Moosylvania
The guts fell out of my muffler at the East Coast rally last year (funny story) It in no way gave me any more power but every one there swore I could better keep up with the wizzers. Honestly, went just as fast by the speedo. The noise is an annoying tinny whine. A wile back I took the guts out of another muffler and attached radiator hose and a lawn mower muffler. MAN! gave it a cool "thump, thump" sound. Really cool but I don't know if it could become flammable. Going to try it again with out the LM muffler and fill the end with chaw boy pot scrubber stuff. To much restriction lowers power.

Removing the guts won't do much good and only bother folks. But loud pipes save lives. (Read that here, but forget whom to give credit to)


Jez, thats cool!! Love the innovation.
 
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Dan

Staff
Staff member
May 25, 2008
12,775
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Moosylvania
Is funny Jason. Just yesterday wile ridding that bike, a gentleman in a pickup turning in to traffic had not seen me and went to go so I revved up twice and he looked to his right and saw me. Not that a lawful "sufficient sound signaling device" would not have worked just as well.
 

eDJ

Member
Jul 8, 2008
530
0
16
Wayne National Forest
Just a point of question here..........doesn't the back pressure of the muffler or expansion chamber of a 2 stroke engine somehow help with controlling the oiling of the motor ? I remember when people were pulling the baffles out of dirt bike mufflers and the dealers were warning them against doing it for prolonged periods of time. (claiming it would lean out the engine...and since the fuel carried the lubricant it would lead to under lubing the moving parts)

Anyone else with a take on this ?

Remember.....I'm saying "Prolonged periods of operation".