To see my pipe have a look at Posters' Picture Gallery #1a.

To see some proper motorcycle exhausts go to Akrapovic.

Clive W  

Ah, you are the expert as well as Ed.  He says that the basic principles apply regardless of the number of cylinders.  Of course, with multiple cylinders there is more gas flowing so that does affect the tube volume required to move the gas at the desired velocity.  It has been awhile since I studied the info he has on the site so I am kind of rusty now.   No need for me to try explaining anything more since you are lightyears ahead of me.  Anyway, for my part I will just do the rough work of trying different sizes and lengths.  My skills are very basic so I will have to use prebent and straight tube...cut and weld...that sort of stuff.
You asked about the pipes I mentioned above...the numbers listed are for inside diameter.

Don't know what happened here





A poor image but a nice short pipe.

Clive W  

I'd like to say thanks but I found it on jons site from the links page.
It is so short (head to silencer) that the pulse probably goes down and up twice to work at just under 5000rpm's. If it only goes down and up once then it would be best at nearly 10000rpm's  

This Shows up on my KLX where the pipe is tuned for 6500 (two steps to spread things out a bit) but also works at 3250 for good torque, and due to the tame cams and small bore of the pipe doesn't fall down in the middle.

Clive W