Exhaust Exhaust system extensions

[try 1897]

So this is a bumblebee bike motor of rear wheel friction drive. I have a rain drive wheel and it's a bit faster top end. The problem is that it makes power with RPMs and the older folks in my area don't care for all the noise. I got an exhaust extension kit to help quiet it down and it did. But what are are the conveniences of restricting the exhaust? I'm not sure if this is a good idea. Any thoughts??Tom

 

[try 1897]

So this is a bumblebee bike motor of rear wheel friction drive. I have a rain drive wheel and it's a bit faster top end. The problem is that it makes power with RPMs and the older folks in my area don't care for all the noise. I got an exhaust extension kit to help quiet it down and it did. But what are are the conveniences of restricting the exhaust? I'm not sure if this is a good idea. Any thoughts??Tom

I tried to ask what are the consequences of extensions or exhaust restrictions on a small 2 stroke but the phone decided to change it. Sorry Tom

 

[try 1897]

Well I burned maybe a qt.of gas at 25 to one and ready to go to 35 to one cause it's new and I'm doing a break in. I'm seeing a gain in power as it is doing so. But the exhaust extension seems to have robbed some power. The new pipe fits into the muffler and directs the exhaust down and is "16 long. So it's smaller. I'm going to try and find the parts to go on the outside of the original pipe and just directs the exhaust down. That should quiet it down some and not restrict the flow. Anyone else tried this? Tom Yendell

 

[Frankenstein]

I tried to ask what are the consequences of extensions or exhaust restrictions on a small 2 stroke but the phone decided to change it. Sorry Tom

Restrictions are killers, basically don't put something more restrictive than what's already there, stacking should be ok if it's as or less restricted than what it uses now, remember air flow is a constant regardless of the length, though, with longer paths the air will crash into itself more so the turbulence adds up after a while. The simple tiny elbow to make the exhaust go this way or that won't affect a thing unless you are talking about 4 feet of tubing. Even then pressurized gas deflates to air pressure nearly instantly so don't be too worried about it unless you have an exhaust restriction that's much smaller than the smallest point in the intake, these 2 strokes are a unique pump that depend less on how much gets away as much as they do on how soon (or not soon) it leaves the chamber.

 

[try 1897]

Thank you. You said what I was thinking If I can make an elbow to direct the flow down and it fits the outside of the original pipe and extend it 5 or 6 inches .that might work. I guess I'll try the hardware store and see what I can make. Thanks again for the help. Tom Yendell

 

[try 1897]

So I silflosed a copper 90 (home made) that directs the exhaust down and extends 4 inches. Attaching to the nipple of the muffler was a bit of a challenge but I got it secured with a bit of bailing wire and it's tight for now. It is slightly larger than the original pipe so it should flow. The total length is seven inches. As far as being quieter? Well it is but not enough. Do you think I can extend it down some and still have the flow? It does seem to have the original power now and runs good. I'm afraid I will restrict it if I go too far. Tom Yendell

 

[Frankenstein]

So I silflosed a copper 90 (home made) that directs the exhaust down and extends 4 inches. Attaching to the nipple of the muffler was a bit of a challenge but I got it secured with a bit of bailing wire and it's tight for now. It is slightly larger than the original pipe so it should flow. The total length is seven inches. As far as being quieter? Well it is but not enough. Do you think I can extend it down some and still have the flow? It does seem to have the original power now and runs good. I'm afraid I will restrict it if I go too far. Tom Yendell

Just don't make it smaller than the smallest tube and it won't be restricted more than it already is.

 

[try 1897]

My concern is that if I go longer I don't want to make it too long and cause a problem. I'm at a total of 7" and one 90 now. I'd like to go 5 more inches if that's possible. Tom