Box Junction, Blocked Exit and a Green Light
You are approaching a signal-controlled crossroads in Colombo. Your signal is green. Beyond the junction, traffic is queued bumper-to-bumper and the exit on your side is partly blocked by a stopped van. A yellow box grid is painted across the junction. A lorry ahead of you has already entered the box and stopped, with its rear overhanging the pedestrian crossing. You intend to turn left. A cyclist is filtering slowly along your left side, between your motorcycle and the kerb. The traffic warden on the far corner is looking elsewhere and is not giving you any signal. Your lane is narrow; there is no separate left-turn slip lane. The light has been green for about 15 seconds and may change soon.
1. Should you follow the lorry into the yellow box? Explain what the box marking requires and how the blocked exit affects your decision.
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No. The yellow box is a keep-clear marking: you may enter only if your exit beyond the box is clear and you can clear the box without stopping. The green light gives you permission to proceed across the stop line, not a right to block the junction. Here the exit is partly blocked by the van and the lorry is already stationary in the box, so following it would leave you stranded on the marking, obstructing cross traffic and the pedestrian crossing. Stop before the box and wait, even if the light is green. If the queue does not move, stay out.
2. How should you manage the cyclist on your left while waiting and when you eventually move?
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The cyclist is on your left and is vulnerable. Do not move left, rev, or squeeze past. Hold your position with a gap of at least 1 m from the kerb side so the cyclist is not trapped. Check your left mirror and blind spot before any movement. When the queue clears, signal left early, let the cyclist go first if they are going straight or left, and turn behind them rather than cutting across. Do not overtake a cyclist immediately before a left turn; a left hook is a common crash.
3. What should you do if the light turns amber while you are still before the box?
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If amber shows while you are still before the stop line and can stop safely, stop. Do not enter the box to beat the light; that would leave you blocking the junction on red. If you have already crossed the stop line and are committed, clear the junction only when your exit is clear; otherwise stop before the box if you can do so safely. The decision depends on your position and stopping distance, not on the desire to avoid waiting.