The hour counting function of the Tiny-Tach TT2A should work out of the box. However, if you want the cool RPM feature to work you will need to verify and set the meter for your engine. The Honda EU2000 is a one cylinder 4 cycle engine. This meter will work on just about any kind of gasoline engine available.
When we played with the setting we kept miscalculating the formula in the TT2A datasheet. In the end, I simply found a setting that matched what I knew the RPM had to be from the generator’s manual.