Overtaking a slow truck before a crest on a regional road
Dmitry rides a 650 cc category A motorcycle on a two-lane regional road outside the city, limit 90 km/h. Ahead of him a grain truck is doing 60 km/h and throwing up grit. The road has one lane in each direction, a solid centre line for the next 300 m, then a broken line, then a crest about 500 m ahead where the road curves left and disappears. There is a bus stop lay-by on the right just before the crest and a side road joins from the right 80 m beyond it. Dmitry's speed is 85 km/h and the truck is 12 m long. He estimates he needs about 8 seconds to complete the overtake at his current speed difference.
1. Can Dmitry legally and safely begin the overtake at the point where the line becomes broken?
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No on both counts. Legally, the solid line forbids crossing, and even after it becomes broken the approach to a crest with restricted visibility is a place where overtaking is prohibited because the rider cannot see oncoming traffic. The junction on the right is a further prohibition: overtaking at an intersection of unequal roads is restricted precisely because a vehicle may turn out. Safely, the arithmetic fails. The closing speed is only 25 km/h, about 7 m/s, so passing a 12 m truck plus a safe return gap takes well over 8 seconds at that pace and covers several hundred metres - more than the distance to the crest. Dmitry should hold back, increase his following gap to at least 3 seconds to escape the grit, and wait for a straight, fully visible section with no junction.
2. What following distance should Dmitry keep behind the truck, and why is the usual two-second rule insufficient here?
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On a dry road the minimum is about 2 seconds; in rain, grit, or reduced visibility it should be doubled to 4 seconds or more. At 85 km/h, 2 seconds is roughly 47 m and 4 seconds about 94 m. The two-second rule assumes good grip and a alert rider. Here the grit reduces tyre grip, the truck blocks the view of the road surface and any hazard ahead, and the spray coats Dmitry's visor. A longer gap restores sight lines, gives room to brake progressively rather than grab the lever, and removes the temptation to overtake impulsively to escape the spray.
3. If Dmitry decides to overtake later on a clear straight, what should he do before, during, and after the manoeuvre?
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Before: confirm the line is broken, no junction or crossing is within the overtaking zone, visibility covers the whole manoeuvre, and no vehicle behind is already overtaking. Check mirrors and blind spot, signal, and move out progressively. During: accelerate decisively so the exposure time is short, keep a lateral gap of at least 1 m from the truck, watch for the truck drifting and for oncoming traffic, and be ready to abort by braking back into the lane. After: do not cut in front; return only when the truck is visible in the mirror, signal, and maintain speed rather than slowing abruptly. In rain, reduce ambition further: the painted centre line and grit both reduce grip during the lane change.