[TR] Electric Fans: Something Different

[Randall]

> So what exactly is the energy co-efficiency of heavy vs. 
> light flywheel?  Heavy means more torque to take you up a 
> steeper hill in higher gear, whereas light means less mass to 
> move on acceleration so prompter speed?  Something like that?

Heavier means the engine has more resistance to sudden changes in speed (aka
inertia).  So you get less drop in rpm when you let the clutch out
(especially on a hill).  Acts like more torque, but isn't really since it
only applies to sudden changes in engine rpm.

But more inertia also limits how quickly the engine can spin up.  It takes
power to accelerate that heavy flywheel, so a lighter flywheel acts like
more power when accelerating (but again isn't really more power, just less
resistance).

A heavier flywheel also tends to damp out the vibration from each cylinder
firing, so the engine seems smoother.

-- Randall