Experiment a success!

Just passing time in the shop today (waiting for paint to dry again)
I decided to try an experiment with my mufflers. A while back I installed a pair of shorty mufflers on my Seca and although I like the sound, they are a tad loud at high speed. So I decided to put a 1/2" washer inside each muffler (in the front against the baffle) and slide the mufflers back on to the header pipes. That did the trick. They are alot better/mellower and not so harsh anymore. It did not make any difference in perfomance, so I left them in. I experimented with different size washers, but the ones with 1/2" hole in them worked out the best.
I may go one step farther (in the future) and weld 1/4" bolts to the washers, so that I can hook them up to a cable (from a remote location) and be able to turn them 90 degrees while riding. Then I can control the sound while riding.
I got the idea when I looked at the latest addition of JC Whitney catolog. They have recently come out with mufflers (for Harleys) that have electrically activated baffles inside them. The rider can open/close the baffles with a electric soleniod switch on the handlebars, to control the sound. I don't need to go that far (using the solenoid idea) and a cable should work just as well. The system I seen in the catolog costs $600+, so I think I will just make my own! This should be interesting. Maybe next winters project, who knows.

 

what made you think of using washers>Just kinda curious.Thanks

 

Beanflicker,
I've been kind of experimenting with different exhaust systems for the past couple years. I like to find the right "sound" out of my pipes on every bike I own. I've done a bunch of reasearch on how different baffle designs work with sound/back preasure ((sound waves for those who want to be politically correct) The washer design has been used by different manufacturers over the years and I always knew they would make a difference in the sound, but not sure how much it would effect the performance. I did find out that they make a difference if they are installed in front of the baffles or in the rear of the baffles. When I install washers in the front of any given muffler, it seems to deaden the volume, but has the same sound quality (tone) If I install the washers in the rear of the baffle, it usually gives a lower tone and a snappy sound.
I may just pull the baffles out of the shorty mufflers today and install the washers in the rear to see what it sounds like...if I feel froggy! >PD<

 

what is the outside diameter of the washer in qustion?

 

Robby,
The washers I used were 1-1/2" outside diameter with 1/2 hole in them. The reason I used that size is because that the inside diameter of the shorty mufflers, so they fit tight inside them. You can experiment with other sizes, but you may have to modify them to fit inside your mufflers.

 

I remember back in the late 60s, early 70s, the Honda 250s and 305 Super Hawks had pipes with washers that you could turn to make the pipes louder or quiet, depending on how they were turned. They had them mounted on the rear of each pipe and had a kind of spring mechanism that kept them tight enough so they would stay closed or open depending where you wanted them.
That gives me the idea to make mine able to be opened or closed by using a cable from the handlebars to control them. That way I can open or close them as I ride. Just an idea. >PD<