Fuel & Delivery
What are Fuel Injectors?
Spray a fine, precisely-timed mist of petrol into the intake tract or cylinder.
Simplified animation — not to scale.
In plain English
Each injector is an electronically controlled valve that opens for milliseconds at a time, atomising fuel into a fine spray so it burns cleanly and completely.
A simple analogy
“A tiny, incredibly precise spray nozzle, firing hundreds of times a minute in perfect time with the engine.”
How it works
The ECU sends an electrical pulse to open the injector for a calculated fraction of a second, letting pressurised fuel spray through a tiny nozzle. Longer pulses mean more fuel; shorter pulses mean less. Dirty or clogged injectors spray unevenly, upsetting the fuel mixture.
Signs of trouble
- ⚠Rough idle or hesitation on throttle
- ⚠Poor fuel economy
- ⚠Misfiring on one cylinder on multi-cylinder bikes
- ⚠Engine management light with an injector fault code
Rough UK cost
£60–£300
Parts: £40–£220
Labour: £20–£100
Always get a written quote. Prices vary by bike, region, and parts brand.
Heads up: Motoautonomy is for general guidance only. If your bike is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.