Small 4 stroke engine?

Dan wrote:
The requirement stated by the original poster was more reliable than a
Rotax. Are we all that sure that a motorcycle engine or a overstressed
lawnmower engine will be even as reliable? Rotax's are pretty damn reliable
if maintained properly.

Actually with selective use of parts and limiting the revs, I am sure
you could modify a lawnmower engine to be reliable and more powerfull.
Not sure it would meet his criteria, and not sure it would be worth the
work. As for as motorcycles, that would be a much safer bet. Many
Honda Gold Wings are driven past 100,000 miles with so so maintenance.
The newer Harley Evo engines will also make it past 100,000 miles but I
don't think you would want that vibration. There are a few V twins
used on some Japanise bikes that are smooth, especially the crotch
rockets.

On 7 Jun 2005 12:23:42 -0700, "Sport Pilot" wrote:

Many
Honda Gold Wings are driven past 100,000 miles with so so maintenance.

While this may be true, and I don't doubt it, (I find it ironic to be
taking the cautious side of the debate given that I'm testing a Ford
V6 for my aircraft's engine) but cruising around at 8 to 10 % power is
not what happens with aircraft engines. Ok, maybe some occasional
hard use and call it 12% power, but were are talking about a Goldwing
here, not a pocket rocket.

I'm not saying auto engines cannot take a continuous 50% power for
hours on end, with frequent calls for 100% power, but they aren't
often asked to do that normally and as I've said so often in the past,
even if it's something other than the long block that fails, a dead
engine is a dead engine. One of the two Goldwing conversions I read
about used the transmission to drive the prop. That setup failed
after a while. Don't know about the other one.

It isn't just the engine that has to keep going, it's the psru, the
prop, the fuel system, the induction system, the ignition system and
the charging system that also have to stand up to hard use.

Corky Scott

Check out the various Yamaha Virago engines. One has been flying
successfully in a "Graham Lee Neuport 17 for a number of years.

In the hovercraft world, there have been many attempts to make use
of motorcycle engines. The issues are very similar to aircraft. A
persistent problem has been power take off from the sprocket. The
sprockets are always in the wrong place or they are adaptable to belt
drive. (Hovercraft should never have chain drives - impossible to keep
clean and properly guard.). The only examples that are competitive from
a power to weight perspective with the gearbox along for the ride are
the 250-400cc ultrahigh rpm sportbike engines that were never even sold
in the US. They absolutely need the gearbox for speed reduction before
the belt drive.
The 4 inline Yamaha engines appearing in water toys and snowmobiles
might be the trick answer. Some come with builtin gear- PSRU which plus
a belt ought to be reliable. The question is, do you want to spend the
money and do you need 140 hp? If so, that would be a low profile, very
high performance answer.
Actually, I am looking forward to someone exploring this one for
the rest of us.

"Chuck" wrote in message
...
Check out the various Yamaha Virago engines. One has been flying
successfully in a "Graham Lee Neuport 17 for a number of years.

I have had a 1982 Virago for five years. It has 80,000 miles total.

I would no more climb into an airplane with a Virago engine than lay down on
a red ant hill. Either way, you're gonna get bit.

Rich "Found by the side of the road more than once" S.

"Corky Scott" wrote in message
...

I'm not saying auto engines cannot take a continuous 50% power for
hours on end, with frequent calls for 100% power, but they aren't
often asked to do that normally and as I've said so often in the past,
even if it's something other than the long block that fails, a dead
engine is a dead engine. One of the two Goldwing conversions I read
about used the transmission to drive the prop. That setup failed
after a while. Don't know about the other one.

It isn't just the engine that has to keep going, it's the psru, the
prop, the fuel system, the induction system, the ignition system and
the charging system that also have to stand up to hard use.

Corky Scott



Of course, Lyc's and Continentals often outlast their accessories too.

Here in Colorado, many folks commute by road from their homes in Summit
County to the Denver Metro area each day. The return trip is a full
throttle climb for an hour or so for a 5000+ foot climb to the Eisenhower
Tunnel. There is no evidence that these engines are failing at a greater
rate than those in more modest duty. Those failures that do occur seem to
be mainly cooling system hoses.

This tells me that given a good engine choice, a good installation and good
maintenance, an auto or motorcycle engine should give good service in an
airplane.

bildan

some of the "Quickie" experimental A/C used the Onan engine from the
rec.vehicle generator set, or semi trailer truck refrigeration unit -
they are 4 cycle horizontally opposed 2 cylinder and air cooled - most
produce around 35 HP and turn slow enough to connect the prop direcly
to the crank. Readily available parts and high quality come with the
deal. besides they look for all the world like and Aeronca C-3 36 HP
engine and that would be cool

wrote:


Richard Rileguarantee
On Tue, 07 Jun 2005 07:17:44 GMT, Anthony W
wrote:


:Have you considered a motorcycle engine? A modern 600cc liquid cooled
:engine puts out around 90 peek BHP and probably a 50 or 60 BHP for
:sustained output. ...

I've considered them, they seem like a good possibility. The only
problem is I can find weights on the web for the bikes overall, but
not the engines alone. ...

The Kawasaki 340 and 440 are in use in Ultralights but I think
they are two-stroke.



I'm fairly sure the 440 is 4 stroke. But I won't guarantee!
Take a look at the Kawasaki Snow mobile engines. Some of them had CVT
drives, basically a automatic transmission with a Constantly Variable
ratio. It might work.
John

"Bill Daniels" wrote in message
...

"Corky Scott" wrote in message
...

I'm not saying auto engines cannot take a continuous 50% power for
hours on end, with frequent calls for 100% power, but they aren't
often asked to do that normally and as I've said so often in the past,
even if it's something other than the long block that fails, a dead
engine is a dead engine. One of the two Goldwing conversions I read
about used the transmission to drive the prop. That setup failed
after a while. Don't know about the other one.

It isn't just the engine that has to keep going, it's the psru, the
prop, the fuel system, the induction system, the ignition system and
the charging system that also have to stand up to hard use.

Corky Scott



Of course, Lyc's and Continentals often outlast their accessories too.

Here in Colorado, many folks commute by road from their homes in Summit
County to the Denver Metro area each day. The return trip is a full
throttle climb for an hour or so for a 5000+ foot climb to the Eisenhower
Tunnel. There is no evidence that these engines are failing at a greater
rate than those in more modest duty. Those failures that do occur seem to
be mainly cooling system hoses.

This tells me that given a good engine choice, a good installation and
good
maintenance, an auto or motorcycle engine should give good service in an
airplane.

bildan

When you say full throttle, do you mean "Tach at the redline, engine working
as hard as it can given the altitude." or "Pedal depressed farther than
usual, turning 3,500 rpm in one of the lower gears."

KB

"Kyle Boatright" wrote in message
...

"Bill Daniels" wrote in message
...

"Corky Scott" wrote in message
...

I'm not saying auto engines cannot take a continuous 50% power for
hours on end, with frequent calls for 100% power, but they aren't
often asked to do that normally and as I've said so often in the past,
even if it's something other than the long block that fails, a dead
engine is a dead engine. One of the two Goldwing conversions I read
about used the transmission to drive the prop. That setup failed
after a while. Don't know about the other one.

It isn't just the engine that has to keep going, it's the psru, the
prop, the fuel system, the induction system, the ignition system and
the charging system that also have to stand up to hard use.

Corky Scott



Of course, Lyc's and Continentals often outlast their accessories too.

Here in Colorado, many folks commute by road from their homes in Summit
County to the Denver Metro area each day. The return trip is a full
throttle climb for an hour or so for a 5000+ foot climb to the
Eisenhower
Tunnel. There is no evidence that these engines are failing at a
greater
rate than those in more modest duty. Those failures that do occur seem
to
be mainly cooling system hoses.

This tells me that given a good engine choice, a good installation and
good
maintenance, an auto or motorcycle engine should give good service in an
airplane.

bildan

When you say full throttle, do you mean "Tach at the redline, engine
working
as hard as it can given the altitude." or "Pedal depressed farther than
usual, turning 3,500 rpm in one of the lower gears."

KB

I mean full throttle in whatever gear will give the most speed - RPM at the
HP peak. Even my V8 Grand Cherokee, if loaded, will require full throttle
on the uphill grades and still be below the speed limit.

The cops are usually smart enough to set speed traps on the downhill grades.

bildan