Night-time overtake on a wet two-lane road
You ride a 125 cc motorcycle at 23:00 on a dry-then-damp two-lane road outside a town; the limit is 90 km/h. Rain stopped 20 minutes ago, the surface is still dark and glossy in patches, and your visor has fine droplets. Ahead, a lorry with two trailers travels at 62 km/h. The centre line is broken on your side, but the road curves gently left 150 m ahead and the lorry's rear lights are bright. Your headlight shows a reflective marker post on the left verge and no oncoming headlights. You are 40 m behind the lorry, in fifth gear at 60 km/h. Your front tyre is two seasons old with 2.2 mm tread depth in the centre grooves.
1. Should you begin the overtake now? Justify with the legal and physical factors.
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No. Three factors combine against it.
Legal: A broken line permits crossing only when you can see the road is clear far enough to complete the manoeuvre safely and without obstructing oncoming traffic. A gentle left curve 150 m ahead hides the far approach; at a closing speed of about 28 km/h (90 − 62) you need roughly 20 seconds to pass a two-trailer lorry, covering about 500 m. You cannot see 500 m through the curve, so the 'clear' condition is not met.
Physical: The damp, glossy patches reduce grip, and the overtake needs acceleration and possibly braking on a surface with less adhesion. Your front tyre at 2.2 mm is legal (minimum 1 mm) but has poor water clearance; a worn front tyre worsens steering response in the wet.
Visibility: Droplets on the visor scatter light from the lorry's bright rear lights, reducing your ability to judge its length and any oncoming glow.
Correct choice: stay 40 m back, wait until the curve opens and the road is visible for at least the full overtaking distance, then reassess.
2. What following distance and lane position would you choose while waiting, and why?
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Hold a gap of at least 3 seconds, and more in the wet. At 62 km/h a 3-second gap is about 52 m; you are at 40 m, which is under 3 seconds, so drop back slightly. This keeps you outside the lorry's spray and gives room to see past its left side.
Position yourself slightly left of the lane centre, but not over the line, to widen your view around the lorry and to be visible in its mirrors. Avoid sitting directly in the spray plume, which coats the visor and reduces contrast. Keep the headlight on dipped beam so you do not blind the lorry driver through the mirrors, and be ready for the lorry to brake for the curve.
3. If you decide to overtake after the curve, what checks and abort criteria apply?
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Before moving out: mirror and shoulder check, confirm no vehicle is already overtaking you, confirm the line is broken on your side, and confirm visibility of at least the full overtaking distance plus a margin.
Abort if: any oncoming headlight appears, the curve tightens more than expected, the surface shows standing water or a glossy sheen across your path, the lorry accelerates or drifts left, or you cannot complete the pass before the next solid-line section or hazard.
During the pass, use a decisive acceleration in the correct gear, keep a margin from the lorry's left side, and return to the lane only when you can see the lorry's cab in your mirror. If in doubt at any point, fall back and wait.