Expert Usenet Opinion Needed

  Aha!

 At work yesterday, I was standing around with the other guys who
ride
to work. They have a seperate parking area for motorcycles at our
office
complex. This is fine by me. it lets us riders hang out together for a
few
minutes after work and keeps the cagers away from the bikes. Anyway,
we were standing around yesterday getting ready to leave talking bike
stuff
and  some guys looking at my new bike, a Yamaha VStar950 and one
of them started the argument..."but it is air cooled, the engine won't
last
nearly as long as a water cooled one".  Now having ridden bikes over
 the years I had never heard that one. Most of my
bikes have been air cooled with a couple of exceptions. The only
difference
that I ever noticed was that I had to check to coolant in the liquid
cooled
ones. I've never had a air cooled one over heat on me even tho I live
in Florida
where it can get pretty warm. And I've never heard of a liquid cooled
engine
lasting longer than an air cooled one. The conversation went on for
awhile with
nobody agreeing to anything and I decided to check with the "experts"
here.
Liquid cooled or Air cooled. Pro or Con?????

Dr Phil

 
We have a local pilot at the airport who is, I believe, 82 years old.  He
rides a motorcycle that is 20 or 30 years old, and is air-cooled.  He has, I
believe, either 38,000 or 78,000 miles on it (I think the latter), and he
brags that he has only ever put tires and chains on it (the engine has never
been apart).

I've never seen anything to suggest that air-cooled engines will die before
water-cooled ones, at least not in a practical time frame.

Now, if you would carry the curve out to failure (which most bikes don't
see), there might be a small difference (more precisely, I mean I can't rule
this out).  Or there might not.  But most motorcycles don't live until
engine failure.  They are retired for other reasons.

For practical purposes ... I don't think there is a difference.

The Lizard

 

And the engines on his aircraft will be...... air cooled and they ARE quite
important to a longish life.

TOG's response was spot on anyway.


--
Beav

VN 750
Zed 1000
OMF# 19

 

  Few air-cooled motorcycle engines are torn down and inspected annually
(at a minimum) with many parts being replaced after a set number of hours
"just because".

  That is not a comment one way or the other as to the longevity of air-
cooled versus water cooled.  You just can't really compare an air cooled
airplane engine to an air cooled motorcycle engine in this respect.

--
RCOS #7
IBA# 11465
http://imagesdesavions.com

 
Good catch.  You are right.

The required typical overhaul interval for a light aircraft (Cessna, etc.)
engine is 2,000 hours of operation.  It is fairly expensive to have this
done (I don't know exactly how expensive, but I'm guessing $5,000 -
$10,000).  This is such a fact of life with aircraft that the purchase price
of a used aircraft depends partly on how long until the next annual
inspection and how long until the next required engine overhaul.  An
airplane that just had its annual and just had its engine overhaul is
probably worth several thousand dollars more as a used plane than one that
needs its annual next month and needs the engine overhauled in 100 more
hours.

It is also noteworthy that the rules require that if you strike the
propeller on anything strong enough to change the RPM, the engine has to be
torn down and inspected (inspect the crankshaft for cracks and all that).
Engines that have struck the prop on something solid have a high failure
rate afterwards if they aren't inspected and repaired.  So, if I run off the
runway and plow down a few weeds and a little grass--no inspection required.
But if I porpoise a landing and strike the propeller on the runway--very
expensive inspection required.

A couple years ago, the Marshall (Michigan) Soaring Club had the landing
gear fail on their glider towplane.  Fortunately, the glider being towed in
the air radio'd to indicate that it looked visually like something was wrong
with the towplane gear (i.e. they were lucky as to how and when it failed).

After releasing the glider, the towplane pilot (a Vietnam F-4 pilot),
circled to burn off as much gas as possible for safety, then came in for a
landing.  When he was sure he could reach the runway, the stopped the engine
and used the starter motor to position the propeller to be horizontal so it
wouldn't strike the ground.  He glided it in and scuffed up the plane a
little (the gear on one side or the other did fail), but the act of stopping
the engine and positioning the propeller horizontal probably saved the
soaring club $10,000 or more.

This was big stuff in Marshall (excitement for the month).  When he landed,
he had a couple firetrucks and an ambulance waiting.  Fortunately, those
weren't necessary.

Anyway, you are right.  With inspection and overhaul rules like there are
with airplanes, the way the engine ages does not matter.  No motorcycle gets
that kind of care.

The Lizard.