What's the original quote? Motorcycles were a common enough piece of equipment both for Wehrmacht, SS or Polizei units. This is in large part due to the fact that in terms of individual motorization, Germany before WWII was largely based on motorcycles, much more so than on cars, and to a larger degree than in any other country that I am aware of. Motorization in inter-war-Germany meant motorcycle-motorization, which meant two things: personal expertise in handling a motorcycle was widespread, and production capabilities for motorcycles were already present. Companies such as BMW, DKW or Zündapp would adapt their civilian models for military use and produce many tens of thousands during the course of the war for use by the Wehrmacht, but civilian models and captured foreign motor-cycles would also be used.

Kradschützen (Krad is a contraction of Kraft-Rad, motor-cycle), or motor-cycle soldiers, were an integral part of German motorized forces, valued for their speed and maneuverability, and batallions of Kradschützen were a part of Panzer- and motorized Infantry divisions, so that's one context where they might appear, at least until 1943 when they were re-formed into reconnaisance units and largely abandoned their motorcycles as main form of transportation.

Kräder would also be used by Kradmelder, motor-cycle-messengers, as a swift and maneuverable form of transportation, and they were in use throughout the German armed forces and the Police and security units in almost any unit as far as I am aware. Consequently, the Einsatzgruppen had motorcycle mounted soldiers as well.

A German soldier or member of the Einsatzgruppen on a motorcycle would not be something unusual, so a bit of context would be helpful.