Puch supermaxi normally only 30-35 kmh but accelerates on long straight stretches sometimes up to about 55 kmh?

The Puch-Maxi series has the technical speciality of being allowed to run in Austria at the plant 40 KM/h, in Switzerland still 30 and in DE only 25 .

If you write, the Mofa already drives about 30-35 in the “normal case” (probably according to the speedometer), then probably something is wrong with the throttle devices, or something is worn or leaked on the engine/cylinder or exhaust. In the case of mechanical contact ignition, the ignition time could no longer be correct due to wear.

Sometimes a small dirt particle in the carburetor can also provide “simply additional power” because of a lean fuel/air mixture.

With increasing wear and leaks, many of the older mofas also tended from Sachs, Zündapp and Kreidler to similar phenomena as described by you, since at that time the speed adjustment of the engine was adjusted only duch flow cross-sections, flow pressure / backflow and mixture formation / ignition time.

The approximately 30 – 35 “normal” (according to Tacho) could be accepted, if necessary, as these old tachos mostly displayed more than actually.

In your own interest, however, you should look at the 40 – 50+ in a temporary appearance as a bigger mistake and the cause for it should be mentioned.