Small Engines (Lawn Mowers, etc.): OVERHEATING, hot summer day, jet pump

Question
Have you ever heard a air cooled engine overheating due to keeping the same rpm or say speed for a long period of time.
for example rideing a bike for 100 miles at 65mph

Answer
Yes I have heard of air cooled engines overheating.  I would like to say however that a "bike" really doesn't fall into the lawn mower category unless its a "mini bike" perhaps.

There are two areas I see overheating at continuous RPM a lot.  In the spring time after an engine has been stored for the winter when mice build nests above the cooling fins.  (I call this a squeaky engine...get it.... mouse...squeak...lol)

And mostly when people don't run the engine at full throttle.  An air cooled engine cools by the amount of air that is "blown" over, into, what ever you want to call it cooling fins.  When the engine does not run at the recommended RPM the flywheel fan simply does not spin fast enough to cool the engine properly.

Think of it like a fan you have in your living room on a hot summer day, when you stand in front of the fan to cool off you most likely want it blowing as fast as it can instead of at low speed don't you?

Where I see this overheating a lot is on pressure washer and jet pump applications.  The engine turns faster then the jet pump can handle so the user compensates by having the engine run slower.  Example..a jet pump is rated at 2000RPM, an engine at 3600 RPM, the user will simply slow the engine down to match the jet pump requirements.

The proper way to resolve this would be to use a 2:1 reduction gear case in which the engine would run at 3600 RPM and the gear case would then turn the crank only 1800 RPM.

Is this all making sense?