This the most expensive and sure fire way to cure the problem.
The different baffles collect the unburned carbon and plug up but you can't easily get to them. Many stock two stroke exhausts have non removable baffles or have only one or two baffles that are removable. If the baffles are not removable it is much harder to clean them. If the exhaust has removable baffles or is fiberglass packed, you can easily clean them and replace the fiberglass packing. This is especially true of quite exhausts. The bike will start easily but just will not rev up. One problem with two stroke exhausts is that they can get plugged up with carbon from the oil used to lubricate the engine. I am assuming he would want you to see this. I have tried to e-mail him but there was no response. I got this from a web site, made by Joseph A. That is why two strokes have such a narrow power band.Ībove is a really nice Gif animation showing how it all works. Running the engine at any RPM above or below the designed RPM and the supercharging effect will be much less effective. There is only one draw back to all this and that is that this supercharging only happens at the specific RPM that the pipe was designed for. Without that properly designed exhaust pipe called an "Expansion Chamber", the two stroke engine will have no real power. This sort of supercharges the engine, giving the high power out put of a two stroke engine. All this happens in three to four thousands of a second. Then, just before the piston closes the exhaust port, this negative wave changes to a positive wave and pushes the fresh intake fuel charge BACK into the cylinder.
This sucks the exhaust AND part of the new intake charge into the exhaust pipe. If the pipe is made just right, a wave with negative pressure reaches the exhaust port just as it is fully open. This wave pressure can be as high as seven pounds per square inch (Both positive and negative waves) and travels at 1600 to 1700 feet per second. Hit another change in diameter and the wave changes back to positive. If it is a positive wave and hits a change in diameter in the tubing of the exhaust pipe it changes to a negative wave. This wave can be either positive or negative in pressure. The exhaust gas rushes out into the header pipe and a pressure wave is created. When combustion occurs in a two stroke, the piston is pushed down by the expanding gases uncovering the exhaust port.
He reportedly said "You'll know when you have the design right, because the chamber will then be impossible to fit on the motorcycle without having it drag the ground, burn the rider's leg, or force the relocation of one or more major components." TestingĪnd finally, after you've tested the bike, we can provide further development in our workshop.¶ Walter Kaaden, the chief engineer for MZ motorcycles in the 1950s, is generally considered the father of the modern two stroke expansion chamber. We fit the pipes to your machine, tuck them in for maximum ground-clearance and make suitable mountings to eliminate unwanted vibration cracking and to improve aerodynamics. Pumping the shapes with oil can make for optimal exhaust gas flow, but only experience defines when, where and how much pressure to use in the fabrication process. We cut the tapered bend shapes and allow for angle changes and even metal stretch. Hand FabricationĪfter the design, we hand-fabricate your pipes using our templates, our design and our experience. The pipe has to work at all the speeds in all the countries you're intending. But that's just how we start your brief - then we recognise the balance between drive and top end power - because a pipe is a compromise. So our starting point is deep expertise and know-how. We have possibly the biggest collection of expansion chamber templates in the world. You're converting a road bike to a racing bike.You're building a bike from scratch and need a specialist exhaust to squeeze every last bit of power out of the engine.
#Custom 2 stroke tuning upgrade
You need to repair or replace original pipes for an exhaust upgrade.You've started to adjust compression ratios or cylinder ports heights and sizes and you need high performance pipes to match the changes.You've rebuilt the entire bike, gearbox, engine or cylinders, and now you need custom pipes.Before anything else, we ask a lot of questions about the bike, its use, how you ride and what challenges you'd like us to overcome.