What is the main danger in riding on bitumen after a rain shower?

Answer: C — Manhole covers and road markings

The main danger when riding on bitumen after a rain shower is related to slipperiness due to contaminants on the road surface. When rain first begins to fall, it can wash away oils and other substances that have accumulated on the road. This creates a slick layer that can make the road very slippery, especially for motorcycles which have a narrower profile and less tire surface contact compared to cars. While manhole covers and road markings can also pose hazards, particularly when wet, the initial rain creates a more widespread problem of reduced traction across the entire surface. Riders should be especially cautious in these conditions as even experienced motorcyclists can lose control if their tires cannot grip the road adequately. In addition, potholes can be dangerous but they are not a direct consequence of rain; they pose a continuing risk regardless of weather conditions. Reduced visibility is a concern as well, but it typically arises from heavier rainfall rather than a light shower, making it less relevant immediately after a brief rain.