You are waiting to turn left and see a motorcycle approaching in the opposite lane, apparently some distance off. What is the safest judgement?

Why D is correct

Motorcycles defeat distance perception in two separate ways at once. Their narrow profile removes the width cue the brain relies on to estimate range, so they do not expand in the visual field at the rate a car does, and their small silhouette against cluttered background makes them easy to miss entirely in the first place. Add closing speed — riders are frequently travelling rather faster than surrounding traffic appears to be — and the safe gap for a left turn grows considerably beyond what would do for a hatchback. When unsure, the correct move is to let the gap go and wait for the next one.

Why the other options are wrong

A. Sound the horn and then complete the turn

The horn tells a rider closing at speed nothing they can act on. What protects them is your decision not to enter their path at all.

B. Turn promptly so the rider has plenty of time to brake

Turning so another road user can brake for you hands the outcome to their reaction time and available grip. Neither belongs to you, and both are worse on two wheels.

C. Treat the gap exactly as you would for a car and turn now

Treating them identically ignores that range judgement depends partly on width. The same physical gap reads as safer than it really is whenever the approaching vehicle happens to be narrow.

On the road

A driver turns left across an approaching rider, having measured the distance against a car-sized outline. The rider was within the limit and had nowhere to go. I did not see them remains the most common sentence in these collision reports.

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