Thanks for the reply Scott,
I am just concerned about giving the front end the nicest life possible with a short hub and only balanced props and spinner. Seems some of them don't fare well, yours is looking good.
The pipe might turn up some results. This cylinder is made for the long run? Chrome or nickle? The piston sounds interesting as well. Could the ports be polished? Very exciting engine, I like your work.
Joe !~)
ORIGINAL: poco242
I have just the one length hub right now. It can not be much shorter than it is because then there would not be enough threads for the prop bolt. As it sits right now the shortest it could be is 5 inches. On most 50cc size planes, the length will not be a problem. Most seem to need closer to 6" or more.
I am trying to find some info on the Echo on a pipe. Nothing yet, but I will modify a header if need be and try it.