Clues needed

[Scot Sealander]

Bruce Plecan wrote:
 
> But, but, wouldn't 600 rpm at 10 mph look the same as 6000 rpm at 100 
> mph??.

Yes, exactly.  That's the point.  It is a gear ratio.  The ratio of
engine speed to vehicle speed.  I am just guessing at what you have,
but the threshold would suggest a decision based on gear.

600 rpm at 4 mph and 6000 rpm at 40 mph would indicate a much lower
gear ratio....

In your first example, the ratio is 60, in the second example, the 
ratio is 150.

Scot Sealander