I have a question for all you tech guys about 2 stroke expansion chambers

What is Cold Pipe Sundrome? It is a term I have heard before about an expansion chamber and negetive effects of cold air around it.Someone please explain it to me.

 

Seems to me Cyclewerksracing.com had an article addressing pipes. Dyno runs are an effective way to test to see how much heat your pipe will run it's best at. Hence the ceramic coatings people apply to them to retain this hp producing heat.

Ken

 

Tuned pipes use the exhaust pressure or pulse to help pull the exhaust gas from the engine. There is a frequency at which the process is most effiencent. If you look at all pipe designs the pipe leaves the engine head and dumps into the largest portion of the pipe or expansion chamber. Further down the pipe the shape tapers into a smaller cone. It is in this tapered area the exhaust pulse is reflected and sent back toward the large expansion area. It hits the large expansion area, combines with the next shot of exhaust coming from the engine and helps pull it away to sent it out the end of the pipe. The repeats is self over and over again. Engine size, operating RPM / peak HP all are taken into consideration when building a pipe.

The frequency changes in the pipe change based upon temperature of the pipe and pipe mfg's build them to be max effiency at operating temperture. That is why a wrapped or a coated pipe tend to stay "hot" all the time the pipe does its best work.

I am not a pipe designer but have read a few articles. There is a lot more math / science to this but it should give you the "jist".