Night Rain, Spray and a Pillion Behind a Lorry
It is 11:30 pm and raining steadily on a two-lane trunk road posted at 90 km/h. You are riding at 70 km/h behind a lorry whose rear lights are blurred by spray, holding a gap of about 40 m, with a pillion passenger on board. You have ridden this road a hundred times in daylight. The surface has polished wheel tracks, fresh tar seams running along the lane, and standing water near the left edge. Your visor keeps misting, so you are seeing the lorry's silhouette more clearly than the road itself. A car behind the lorry starts to overtake, then pulls back into your lane roughly 25 m ahead of you and brakes hard. Your motorcycle has no ABS; tyre pressures and brakes were checked a month ago.
1. Describe your braking and body sequence in the first two seconds, and explain why each choice matters on this surface.
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Roll off the throttle smoothly rather than chopping it, because closing the throttle abruptly on a wet tar seam can break rear grip before the brakes are even applied. Then load the front tyre with a light initial squeeze, pause while the weight transfers, and squeeze progressively harder, adding the rear at the same time. Do not grab: on a polished, wet surface a locked front wheel puts you down in well under a second, and no ABS is there to save it. Keep the machine upright and stay off the tar seams while the brakes are working - braking while leaned on a seam is the classic wet-weather fall. Warn the pillion to brace and stay still, because a shifting passenger mid-brake alters the balance you are relying on. Finally, look past the car to the gap beside it, not at its bumper: target fixation stops riders steering around hazards they had room to avoid.
2. Your gap was 40 m. Use the numbers to judge whether that was appropriate, and state what the gap should have been.
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Do the arithmetic instead of trusting feel. At 70 km/h you cover about 19.4 m every second. The dry-weather two-second rule puts a minimum safe gap near 39 m, so your 40 m was, at absolute best, a dry-road gap. You were on a wet, polished surface at night behind a vehicle throwing spray, and wet conditions roughly double the gap - about 80 m, or four seconds, is the realistic figure. The spray matters as much as the friction: you could not see the hazard early enough to use even a perfect 40 m, so your gap was really decided by the lorry's spray rather than by your brakes. The pillion adds mass, so both tyres and brakes have more to stop, and without ABS a locked wheel stays a live possibility. If the car had braked half a second earlier, you would already have hit it - that is the definition of too close.
3. What would you change for the same trip tomorrow night, and what would you change about the machine?
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Change the plan before changing anything on the bike. Drop your cruising speed to 55–60 km/h, which cuts kinetic energy sharply and buys thinking time; hold a four-second gap and let the lorry go if necessary, because arriving five minutes later is the cheapest safety device available. Ride in the cleaner, less polished part of the lane and away from the standing water at the left edge, and read the surface by its sheen - reflective patches are water, dull patches are grip. Deal with the visor properly: an anti-fog insert, a slightly cracked visor at low speed, and a glove wipe at the first sign of misting, because a rider who can see only a silhouette is riding on memory. On the machine, check pad thickness and fluid level, look for cracking or glazing, and test the brakes at walking pace before joining the main road.