Lane Position Behind a Truck and a Left-Turning Car
Tomas is riding a motorcycle on a four-lane road with two lanes in each direction. Ahead of him in the right lane is a large box truck. In the oncoming left lane, a sedan has its left turn signal on and is creeping forward, apparently waiting to turn across Tomas's lanes. Tomas is in the right lane about three car-lengths behind the truck, positioned in the center of his lane. Traffic behind him is moderate. He wants to pass the truck but the sedan's turn creates uncertainty. He considers moving to the left lane to get a better view and to be seen.
1. Assess Tomas's current lane position and following distance, and explain the visibility problem.
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Three car-lengths behind a box truck in the lane center is a poor setup.
Problems:
- Following distance: three car-lengths at road speed is too close for a motorcycle behind a large vehicle that blocks forward view. The rider cannot see road hazards, debris, or stopped traffic ahead of the truck, and the truck driver cannot see the motorcycle in the mirrors at that gap.
- Lane position: the center of the lane directly behind the truck puts Tomas in the truck's blind spot and in the worst place for forward visibility. A better position is offset to the left of the lane (within the lane) to see past the truck's left side and to be visible in the truck's left mirror.
- Escape route: directly behind a large vehicle leaves no shoulder or gap to swerve into if the truck brakes suddenly.
Fix: increase the gap substantially, offset within the lane to improve sight lines, and only then consider a pass.
2. The oncoming sedan is signaling a left turn across Tomas's path. Should Tomas move to the left lane to pass the truck now? Explain the judgment.
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No - not yet. The left-turn signal from oncoming traffic is a direct warning that a vehicle may cross Tomas's lanes. Moving left to pass the truck would put Tomas closer to that crossing path and reduce his reaction margin.
Reasoning:
- The oncoming turn is the dominant hazard. A left-turning car crossing a rider's path is a classic collision pattern; the sedan's driver may misjudge a motorcycle's speed and distance.
- Passing the truck now compounds risk. A pass means accelerating into the space beside the truck - exactly where the turning car may arrive. It also removes the truck as a barrier between Tomas and the oncoming lane.
- Correct sequence: hold back, increase the gap, watch the sedan's wheels and the driver, and do not commit to the pass until the sedan has either completed its turn or clearly stopped/yielded. If the sedan turns, Tomas has time and space. If it waits, he can then pass with a clear view.
Exam principle: when an oncoming left-turner is present, slow and cover, don't accelerate into the conflict.