Call to discuss your bike
tel:+64 (0)7 543 2299
fax: + 64 (0)7 543 2286
cel: +64 (0)27 6340 327
or just email

A muffler does 2 things.  It changes the quality of sound coming from the engine exhaust and it controls the flow of gases, either increasing or reducing performance.

As the piston moves down the cylinder exhaust gas is released through the open valves.  The gas travels at speeds over 100m/s but more importantly it creates a pressure wave that travels at the speed of sound.  That pressure wave creates noise.  By having a long expanding pipe the gases have room to expand and cool, reducing the pressure and noise.

This pressure wave travels along the exhaust pipe and out but also reflects back up the pipe and the harmonic it creates when it interacts with the next cycle can improve or reduce engine performance, and often both.  At certain revs performance (power) may be increased for a particular engine while at other revs it may be reduced. 

Configuration of the exhaust tube design plus the introduction of chambers and baffles (mufflers) can even this out, thus increasing power where you may want it most without necessarily losing power in other places.

Mufflers can be designed to either dissipate the noise or reflect it back in such a way that the sound waves cancel each other out.  It's quite literally rocket science since you are dealing with expanding gases and pressures, and designing chambers to accomodate those.  Get it right and your bike has increased performance and a rumble that turns heads.  Get it wrong and you become public enemy number 1.

Most mufflers have three chambers with damping tubes coming from them.  While this is effective in noise reduction, it can impact on performance.  A free flowing system enables better performance but results in excessive noise.  To get the best compromise we design and build our own damping tubes and pack the system with materials that absorb the unpleasant higher noises while leaving the lower sounds.

If all this sounds complicated you can rest assured that each Classic & Custom Motorcycle Mufflers and Exhausts system is carefully designed and measured to your bike and hand built to the highest quality leaving you not only with a perfect and fantastic looking muffler but one that is truly unique.