Night Rain on a Blind Crest
It is 22:40 and raining steadily. You are riding a 400 cc standard motorcycle on a two-lane rural road posted at 80 km/h. Your visor is beaded and your headlight throws a short, bright pool about 25 m ahead before the beam fades. The road climbs to a crest where a faded solid centre line runs along your side, and beyond the crest you cannot see the surface. Your rear tyre has 2.5 mm of tread left in the centre; the legal minimum where you ride is 1.6 mm. You have been riding for 5 hours with one 15-minute stop, and your last coffee was an hour ago. Traffic is light but a lorry has been following at roughly 30 m for the past 4 km.
1. Using the stopping-distance and visibility information, decide what speed and lane position you should adopt before the crest, and justify it.
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At 80 km/h you cover about 22 m every second, and your total stopping distance on wet tarmac is well beyond the 25 m of usable light. You are effectively over-riding your headlight: by the time an obstacle appears at the edge of the beam you cannot stop before it. The faded solid line also means no overtaking and warns of restricted visibility.
Practical response:
- Reduce speed to roughly 50–60 km/h so stopping distance fits inside the illuminated zone, and slow further if the surface looks glossy.
- Move toward the centre of your lane but stay left of the centre line, keeping a margin from the oncoming side while avoiding the oily strip in the middle.
- Use the lorry's headlights as a secondary cue: if its beam pattern changes, something is ahead.
- Do not overtake or creep over the crest; wait until the road beyond is visible before resuming speed.
The judgement being tested is matching speed to what you can see, not to the posted limit.
2. The lorry behind is close and your fatigue is building. What sequence of actions reduces risk without creating a new hazard?
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A tailgating lorry plus fatigue is a compounding problem, and braking abruptly would invite a rear-end collision.
Sequence:
- Signal early and slow gradually using engine braking and light brake pressure so the lorry has time to react.
- Create an escape route: keep the left portion of your lane so you have room to move right if the lorry closes, and never sit directly behind a vehicle you cannot see past.
- Let the lorry pass at the first safe straight, or pull into a lay-by and stop for 15–20 minutes. Fatigue is a legal and safety issue, not just discomfort; continuing while drowsy is a recognised impairment.
- Fix visibility first: clear the visor at the next safe stop and consider raising the beam if it is legal and does not dazzle oncoming traffic.
- Check the rear tyre at the stop. 2.5 mm is legal but marginal for wet riding; plan replacement.
The correct answer prioritises predictable, gradual speed changes and separating yourself from the tailgater rather than simply speeding up to escape.