Topic: exhaust note bike to bike

[Don R]

 I rode all of the running bikes back to back to flush the winter storage gas out. The main difference was the difference between the exhaust note on the stock sandcast and the 836 engine in the diecast. The 836 is a lot throatier while the sandcast is higher pitched. They are both geared the same and have fresh 4-4 no number pipes so the modifications (bore, cam, porting) made all the difference.
 I remember the sandcast with 4-2 hookers sounding like an indy car, the same headers and mufflers on a k2 with an unknown size big bore motor are just loud. I assumed the difference was time and burned baffles, maybe not. 

[kerryb]

Very interesting observations, as I've been trying different baffles on another 4 cylinder bike I have.  My original goal was to quiet down  an exhaust note that was harsh and "cackled".  With new glass-wrapped baffles, the sound is mellower, and the sharp "cackle" is gone, but the noise levelis still up there.  After much reading and searching, all I can say is what an interesting science acoustics is.
When you say one of yours sounds like an indy car, do you mean higher piched howl or something else?

[Don R]

 Yes, going through the gears the sandcast engine had a much higher and peppier sound then the same pipe on the K2 unknown CC's over bore motor. I asked the engine builder but he didn't remember which kit he used since often the 836's were sold out.  Might be a second over but he couldn't say for sure.
  The day I was riding the sandy I may have gotten a bit over the top, it was the first ride of the year and got it up to 95 mph  on the way home. I thought better it when I remembered it had storage fuel in it. My buddy called later to rave about how good it sounded when I was leaving his house.