Quote:
Originally Posted by Huck369
They also run expansion chambers on 4-Strokes, they are different than the 2-Stroke one, but the bigger section on the header is an expansion chamber, all the performance 4-Stokes systems have them, and the Templar has one on the stock system.... It smooths out the pulses, allowing the exhaust to flow smoother
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No. An expansion chamber on a 2-stroke is a reduction in back pressure implemented with an expanding diameter into a chamber to baffle the impact of explosions from the exhaust port. The chamber reduces in inner diameter to a rat tail with or without a muffler. The expansion chamber reduces intake pressure, and increases power output of the engine. It is very effective in a 2-stroke application. It is an obvious feature on 2-stroke bikes. And I can tell you from experience, it works! But I believe the evidence too!
In a 4 stroke bike, the expansion chamber is a megaphone at the tip of the exhaust (the muffler). There is no expansion "chamber" on a 4 stroke bike. There can be a "collector" which is a broadened but extremely short section of pipe ~2x or 4x the diameter of each individual headpipe in a multicylinder engine (2 cylinder or 4 cylinder), which goes into the muffler segment (which can be a megaphone). On a single cylinder bike, the "expansion chamber" is the muffler (or megaphone).