You notice that one of your tyres has a bulge in the side wall. What will happen if you drive the vehicle?
- A Your tachograph reading will not be accurate
- B Your speedometer will give an incorrect reading
- C The vehicle will become unstable on corners
- D You'll break the law and risk prosecution
Why this is the answer
It's a legal requirement that your tyres have at least the minimum permitted depth of tread and are in good condition before you start any journey. Make sure that you inspect them before setting off, and at regular intervals.
Why the other answers don't fit
- A
- Your tachograph reading will not be accurate — The tachograph records time and speed, not tyre condition.
- B
- Your speedometer will give an incorrect reading — A bulge does not change the rolling radius enough to matter to the speedometer.
- C
- The vehicle will become unstable on corners — Instability may follow, and the first certainty is that the tyre is illegal.
Where this comes from
- Driving Buses and Coaches — section 11
- Driving Goods Vehicles — section 11
Rule numbers link to The Highway Code on gov.uk.
Where this question comes from
The question, its options and the explanation are reproduced word for word from the DVSA revision question bank under licence. The licence requires them to appear unaltered, so we cannot reword them and neither can anyone else — that is why you will meet the same wording on other sites. Everything else on this page is written by Theory Hub: the explanation of why each wrong answer is wrong, the topic guide and the revision notes.
Asked in: Lorry & Bus (LGV/PCV)
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