500 domi racer exhaust

Looking for some help with the dark art of exhaust running.
In the photos is a white ring inside the silencer is this where the pulse ends in the exhaust?
If So where should it be ending in the silencer or out of it?

AFAIK… if it was an open mega, that mark would be telling you where to cut it.

But in a large ID, parallel, perforated tube, I do not believe it makes any difference to performance, and if you did cut it there, all you’d do is make it louder.

Is it by NRP? If so discuss with Nigel, he knows a fair bit about this black magic.

ACCORDING TO THIS ,


You Put your crayon or paint line , along the pipes , Which will give you the pulse length as it burns off .
If the pipes 100 feet long , youl get twenty or so , which will work best , as its Multiple , so a broader
powerband . And you cut it at the BURNT SPOT . Under a car you might get three or four pulse multiple.

Maybe TWO on a cycle .

Youll let us know , then .

I think paint would be less likely to discolour the chrome , than crayon . So dont do it where it'll be glareingly obvious if it does .

My exhaust system is painted black and has no paint for about 200mm after the port. I have thought about what you are saying. I have been very careful to make sure there are no steps where gas exits from the cylinder head. Walter Kaden worked on the pulse jets for the German V1 bombs. The tail-pipe on my exhaust system has the same crossectional area as the sum of the two header pipes, and the tail-pipe length is the same as for one of the header pipes. I suggest the tail resonates at twice the frequency of a header pipe, so the pulses should work constructively. When I ride the bike, there are no sudden power bumps - it pulls smoothly and strongly everywhere. It is what is needed for fast cornering.
When you are in a corner, your speed is moderated by feel - light in the front, under-steer and power bumps - all make us go slower. The fear factor is caused by adrenalin - it is a nuisance, not a help.