How Can I Tell If I Have Got My Pocket Bike's Fuel Mixture Right.

The condition of the spark plug can reveal much about the engine's state of health in much the same way as a doctor takes a blood sample while conducting a medical.

Under normal circumstances, the spark plug should appear a light brown or golden colour. If the electrode is white, this indicates the engine is running too hot. Usually this is because the carburetor is running too lean (not getting sufficient fuel) or that the petrol and oil mix is too weak. Too rich a mix of petrol and oil and the spark plug will be covered in black sooty deposits.

Another common problem with spark plugs is fouling. The plug becomes covered in black gloop and this is normally because of an incorrect gap setting.

The conclusion to be drawn from anything other than a dark brown or golden coloured spark plug is an urgent need for some pocket bike TLC.