Originally Posted by MTK

No, the YS 4 stroke puts out hotter exhaust than gasoline 2 strokes. I have designed-in additional cooling to the exhaust system and the engine, not because the engine runs hot but rather for noise reduction. Cooler exhaust is quieter. The baffling I show in the video wasn't necessary, at least not in NJ. I simply wanted the engine cooled more inside a cowl; full power never bogs the engine down from too much heat. If I lived in too hot Texas or any of the southern states, summers might get the engine too hot, I don't know. On the other hand, I never use full power for any sequence. Half throttle is where the engine lives, between 4K and 6K rpm.

I use the ESComposites carbon composite pipes and highly recommend them. Never any problems; just don't get hot enough. But I also know that Ed Skorepa, Mr. ESC, no longer offers his carbon mufflers for 4 strokes because guys were burning through the epoxy he uses. It was likely a combination of too hot exhaust and poor cooling design.

Using gasoline I had to develop my own pipe couplers since most anything else readily available that I tried (plain silicone or Teflon) did not perform to my satisfaction. I've described this elsewhere in other threads so need to repeat here. This thread has been hijacked enough probably. We can take further discussion directly to emails...





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