| Author | Message | ||
     Johnboy777 |
I recently purchased an XB12 muffler from a forum member here and dissected to understand how it works. The drawings below show how the valve operates within the muffler, in the open and closed positions. In the valve open position, what you essentially have a straight pipe which runs from the small front expansion chamber of the muffler through the muffler and out the tail pipe. So that the exhaust leaves the header and enters the front expansion chamber of the muffler, then travels straight out and exists the rear of the muffler... a nice clean shot. The valve closed position is a maze for the exhaust gases and they travel down the length of the muffler from the header into the rear expansion chamber ,then move back-to-front, as they travel to the front expansion chamber where they slam into the matting at the front of the front expansion chamber (via a perforated wall that houses the matting)and then from the front expansion chamber travel back down the length of the muffler once again, and out the muffler's tail pipe. I guess the question I have after looking at this, is why not simply wire the muffler valve open, if you want a loud exhaust, after disconnecting the servo cable at the muffler or at the servo? The servo doesn't know its NOT opening and closing the muffler valve - the ECM only reads servo operation - it has no way to confirm whether or not the muffler valve is actually operating. Of course, you can always go back and re-connect it at a later date, if you get tired of loud... just a thought. VALVE IN THE CLOSED POSITION:  VALVE IN THE OPEN POSITION:  John H. | ||
| Dio |
Is there a chance that this is what the "Drummer" boys do, since there is a new end cap on the muffler body when you get it back? | ||
| Wolfridgerider |
 From what I could tell, this is what a drummer kinda looks like before it gets packing and the end cap. | ||
| Towjam |
I guess the question I have after looking at this, is why not simply wire the muffler valve open, if you want a loud exhaust, after disconnecting the servo cable at the muffler or at the servo? If memory serves me correct, this was discussed in a Fuell article. I don't remember which specific issue but I think it was circa '05 if you care to download 'em from buell.com. | ||
| Dio |
How did you happen on to this slick photo? | ||
| Growl |
I experimented with securing the valve open and it doesn't really make the bike all that much louder - yes some - but not much... It does however, noticeably make mid range power go down. | ||
| Wolfridgerider |
Slick photo 101 http://www.badweatherbikers.com/buell/messages/406 2/335464.html?1203900481 |
