What does a catalytic converter reduce?
- A Exhaust noise
- B Fuel consumption
- C Exhaust emissions
- D Engine noise
Why this is the answer
Catalytic converters reduce the toxic and polluting gases given out by the engine. Never use leaded or lead-replacement petrol in a motorcycle with a catalytic converter; even one tankful can permanently damage the system.
Why the other answers don't fit
- A
- Exhaust noise — Exhaust noise is dealt with by the silencer, which is a separate part of the system.
- B
- Fuel consumption — Fuel use is barely changed. What changes is what comes out of the pipe.
- D
- Engine noise — Engine noise comes from the engine itself and is not what the converter works on.
Where this comes from
- Riding: the essential skills — section 17
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: Motorcycle
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