I purchased a Kohler "Tiny Tach" this past weekend to use on my Toro Z Master 257. I was wondering what kind of RPM's everyone else is pushing with their engines? I have a 27 Hp Kohler engine that has the engine NO LOAD RPM tolerance of 3,750 (+,-) 50 RPM's. My buddy is running his Dixie Chopper engine at 4,000 RPM's! Is this to hard for the engine??? Thanks!