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Hello all. I've had a 2008 Yamaha YBR 125 for over a year and it has run perfectly with no problems until recently. The problem is it sometimes refuses to start (electric, kick or push). I'm not mechanically minded so please forgive me if I use the wrong terms but when it refuses the engine tries to turn but doesn't fire / ignite. I've replaced the spark plug and fully charged the battery but this has made no difference. My friend had a look over it checking all wires and connections and even tried it with 'easy start' spray but it wouldn't start. However the problem is intermittent. When it starts it runs fine. When it doesn't start it will later start without having moved or touched it since the last fail. Does anyone have any idea what the problem might be? Many thanks in advance.