Flex Pipe Vs Echo Tube
The echo tube is a considerably less restrictive exhaust system than the flex pipe, as it has no baffle, and is simply a wide open hard pipe. The Flex Pipe acts like a smaller tube (more restrictive) than a hard pipe due to its irregular inner surface, and in combination, the little fishtale tip on the flex pipe is quite restrictive since it has both an internal baffle and a small elongated outlet. The vintage Whizzer engines, as well as the modern ones, have a considerable restriction in the torturous exhaust port/manifold path, let alone adding insult to injury with the installation of a Flex Pipe and fish tale. I would personally eliminate the back pressure and let it breath. It'll run cooler and be happier with the Echo Tube. The Flex Pipe/fishtale combo is very quiet and the Echo tube is much louder (sounds geat to my deaf ears). So the question for Dear Abby - should the rider be happy with the low cost Flex Pipe, or should the engine be happy the expensive Echo Tube? I don't think Ole Abby can handle this one so it will be on you to decide.