Two-lane roundabout with a lorry in the outside lane
You are approaching a large two-lane roundabout with four exits, in a country where traffic keeps right. You intend to take the third exit, effectively turning right around the circle. You are in the left-hand lane, which is the inner lane for this manoeuvre. A articulated lorry is in the right-hand, outer lane beside you, slightly ahead, and its left indicator is flashing. A small car is following you closely. The roundabout has clear lane markings but no traffic lights, and traffic on the roundabout has priority.
1. Explain your lane choice, your signals and the checks you make before entering and while circulating.
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For a third exit I would normally use the inner, left-hand lane on approach, signalling right to show I am going beyond the halfway point. Before entering I would check the right mirror and blind spot for traffic already on the roundabout, give way to it, and confirm the lorry's position. The lorry is in the outer lane with its left indicator on, which suggests it may be leaving at the first or second exit, but a long vehicle can also straddle lanes or need extra room, so I would not assume. While circulating I would keep checking the right mirror, maintain my lane, and plan to signal left after passing the exit before mine so following traffic knows I am leaving. The car close behind means I should signal early and brake gently rather than late.
2. The lorry's indicator suggests it may exit before you, but it is long and slightly ahead. How do you decide when to move to the outer lane to leave?
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I would treat the lorry's signal as a clue, not a guarantee. A long vehicle can swing wide on exit and may need the outer lane or even part of the inner lane. My decision to move out would depend on seeing a clear gap in the outer lane, confirmed in the right mirror and blind spot, and on the lorry actually beginning to follow the curve of its exit. If the lorry is still beside me or its trailer is still crossing my path, I would stay in the inner lane and go round again rather than cut across it. Going round a second time is a minor inconvenience; crossing the path of an articulated lorry is a serious risk. I would signal left once I am committed to leaving and check the mirror again before the exit.
3. The car behind is tailgating. How does that affect your speed, signals and positioning on the roundabout?
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A tailgater limits how hard I can brake, so I would reduce my approach speed earlier and more smoothly, using engine braking and gentle pressure so my brake lights come on in good time. I would signal earlier than usual so the following driver has more warning of my intentions. On the roundabout I would keep a steady, predictable line in my lane rather than drifting, and avoid sudden lane changes that could surprise a close follower. If the car remains very close, I would increase the gap ahead of me so that any hazard ahead can be handled with gradual braking. I would not speed up to escape it, because that raises the risk at the exits. If necessary, I would let it pass once I am safely through the roundabout.