David

Many years ago, someone told me that motorcycle engines had a lot of
vibration and for that reason were not really reliable for use in a
very light aircraft that their horsepower would pull. Vibrations
caused failures in the structure????

One data point FYI.

Big John


On Fri, 19 Sep 2003 10:06:41 GMT, David Hill
wrote:

I'm working on a replica of a 1924 airplane originally powered by an
Indian Chief motorcycle engine. I've spent a year or two trying to find
a modern engine that somewhat resembles the Indian, and the best I have
come up with is a Harley-Davidson.

Looks like with an 80 cid Evolution engine I can get ~40 hp at ~3400 rpm
(direct drive) or ~60 hp at ~4500 rpm (PSRU setup).

Has anyone here tried this? Or know of anyone who has done this? I'm
looking for caveats, tips, and techniques. Based on experience, not
opinion. Oh, sorry, I forgot where I was. grin