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Motorcycles and Misfuelling: A Growing Problem in New Zealand

Motorcycle misfuelling incidents are on the rise in New Zealand. Here is why, what the consequences are for a motorcycle's engine, and what to do if it happens to you.

14 October 20254 min read

Why Motorcyclists Are at Risk

Motorcycles in New Zealand are overwhelmingly petrol-powered, but the growth of diesel-powered adventure tourers and commuter bikes — and the increasing presence of diesel scooters imported from Europe and Asia — has created a new misfuel risk category. More significantly, motorcycle riders who own multiple vehicles — a diesel car and a petrol motorcycle — are at elevated risk of fuel type confusion during a routine fill.

What Diesel Does to a Petrol Motorcycle Engine

Diesel in a petrol motorcycle engine causes fouled spark plugs, misfiring, and in most cases immediate stalling. The engine will not run well on diesel, which provides a faster warning than in a diesel car with petrol contamination. However, starting a motorcycle on a diesel-contaminated mixture and riding even a short distance will contaminate the fuel system and may require carburettor or fuel injector cleaning, a full flush, and in some cases, plug and injector replacement.

Immediate Response

If you notice your motorcycle running strangely after refuelling, pull over immediately and do not restart. Call EEK Mechanical on 0800 769 000 — our technicians can assist with motorcycle misfuel recovery in most New Zealand locations.

Need help right now?

Our team is available 24/7 to help with misfuelling emergencies.

0800 769 000