Unless you've already got one, don't mind the craft shaking
itself apart from the inherent imbalance, and can live with the cylinders
frying themselves, think something other than a harley engine. Air cooled
engines work poorly in automobiles, less poorly in motorcycles, and
moderately poorly in airplanes. The inherent problem is that making power
makes *lots* of heat, and in order to remove it with an air-cooled engine
you need a large temperature gradient. This requires CHTs on the order of
400 degrees, extra-special valve construction and materials, cylinder
barrel choke, higher octane requirements, etc, etc. If one's going to go
with something that isn't certified, at least use the best technology
available and use liquid cooling. Cooler, more efficient, roughly the
same weight, less cooling drag, etc, etc. I'm partial to the EA-81 Subaru
engine, but of course I use the same one in my daily driver car...

-Cory

Ken Sandyeggo wrote:
: Second hand caveat: This topic has been beaten to death, buried,
: resurrected and beaten to death several more times on the gyro forum.
: As I recall, the problem is heat. Running at the rpm we need to spin a
: prop is too much for a motorcycle engine. After initial acceleration,
: they basically loaf down the road. The sustained revs will fry them.
: This what I recall being posted by people who seemed to know what they
: were talking about. Craig Wall had some very spirited and seemingly
: logical and convincing posts as to why they won't work. But then
: again, someone may prove them wrong and get one to successfully
: perform. I don't believe anyone has a good handle on it yet, with
: proven reliability over a substantial amount of hours.

: Ken J. - SDCAUSA

--
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* The prime directive of Linux: *
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* (Just my 20 USm$) *
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