Are you allowed in this situation to overtake a single-track motorcycle if you are driving a multi-track motorcycle?

In the photo you are driving on a road outside a town; in front of you there is a single-track motorcycle, and on the right there is sign B-25 "no overtaking". When driving a multi-track motorcycle, you are allowed to overtake this two-wheeler. The answer is: yes.

The Regulation on road signs and signals states that sign B-25 "no overtaking" prohibits drivers of power-driven vehicles from overtaking multi-track power-driven vehicles. So the ban has two sides: it applies to every driver of a power-driven vehicle - also a multi-track motorcycle, for example one with a sidecar or a three-wheeler - but it covers only overtaking multi-track vehicles. The single-track motorcycle in front of you is not a multi-track vehicle, so the sign does not prohibit overtaking it; in the same way, after B-25 you may overtake a bicycle, a moped or a scooter. However, the general rules apply: the distance from the motorcycle being overtaken must not be less than 1 m, before the manoeuvre you make sure that you have visibility and space, and the broken line in the photo allows you to move onto the left side of the roadway. If a car were driving in front of you, sign B-25 would prohibit overtaking.

Legal basis: § 23 para. 1 of the Regulation on road signs and signals; Art. 24 para. 2 and Art. 2 point 32 and 45 of the Road Traffic Act (Prawo o ruchu drogowym)