Final answer:
You should maintain a safe following distance when driving behind a bicycle, often using the "three-second rule" and adjusting for visibility conditions, increasing the distance at night or when visibility is poor to ensure road safety.
Step-by-step explanation:
When driving, it is important to maintain a safe following distance to ensure that you can react in time to vehicles ahead of you, including bicycles. Since bicycle tail lights are not as bright as headlights on your car, you need to be able to see them from a considerable distance to ensure safety. The exact distance may vary depending upon road conditions, speed, and visibility, but a general rule of thumb for driving at night is to stay far enough behind so that you can stop safely within your illuminated area — typically, this would mean staying several car lengths back. As a cyclist's tail light may be dimmer than car lights, increasing that distance even further when following a bicycle is advisable to account for any sudden stops or turns they might make.
Defensive driving courses often recommend using the "three-second rule," which means staying far enough behind the vehicle in front of you so that you pass a fixed point at least three seconds after it does. This could be longer at night or in poor visibility conditions. For bicycles, due to their lower visibility, you might want to increase this to a four- or five-second following distance, adjusting as necessary for safety on the road.