Yes, Ive seen the graphs, and there is another also.
They show the later engine styles in governed form, and are correct as shown, but have no relevance to the engine fitted to the Amplion/unkown.
The First generation 125 as fitted to rotomo and the 3.6hp 125 as fitted to Auto and Model 5 special are ungoverned and therefore have higher power outputs close to those claimed. And With the addition of the Amal carb, even greater performance would be achieved.
We are talking about early generation engines where pollution,economy,durablity etc were less of a concern and "More Power" Meant everything when selling early machines.
Rev ranges for earlier Victa machines were not governed,and relied solely on throttle position and carby size allowing a far greater rev range to be achieved. Then with the addition of the Amal, even more performance would be achieved over the standard 125, making these HP and Rev claims in the advert pretty close IMO...
I guess, the main point here was the Question.... was it even necessary or safe?
Not really, This is one of a few reasons why engines became governed,(Ever felt and heard a Special at full throttle!lols) but at the time this is what technology allowed.
These early mowers are from an era where the toe guard was barely thought of, And "More Power"Claims sold machines, a far cry from the more modern technology of the safer,quieter,more fuel efficient and reliable 70 series machines.
In any case I still think these ratings are fairly accurate to the Victa 125 fitted Mower in the Advert....but not of those on the later 70 and 80 series governed engines in your graph where a lower Hp rating is seen and the optimal rev range is 3200-3500 rpm.
