[North Dakota]

The hour meters on tractors record hours at different rates based on the RPM of the engine. The hour meter should read pretty close to regular time at a certian RPM (most likely different for each size of tractor and engine type/size) Any RPM above the tractor norm will read faster then normal time anything less it will read slower. I think my Manual states that somewhere around 2000 RPM is normal tractor operating RPM.