KMX125 won’t kick into life

By MCN -

Parts & accessories

 26 November 2012 15:44

Q. My fairly ancient Kawasaki KMX125 two-stroke won't turn over, however hard I stamp on the kickstart, after I left it outside with a rain cover on for six weeks.
Lovebikes25, MCN forums

A. That doesn’t sound like long enough for corrosion to have set in and seized it up. But what might have happened is that you have a hydraulic lock.

This can happen if the fuel tap has been left on, and the pressure of the fuel eases past a (probably dirty) float needle in the carb float bowl, flooding the cylinder.

When you try to kickstart it you are trying to compress the neat fuel which will become a solid mass, stopping the piston from rotating over the compression stroke.

Take the spark plug out and see if it turns over. If it does, kick it over until no more fuel comes out of the spark plug hole, then screw a clean and dry spark plug back in.

If you find the spark plug just gets wet with fuel all the time and the bike will not start, then the crankcase is also flooded.

The quickest way to sort this without stripping it all down is to take the fuel tank off and with several mates to help, turn the bike upside down and with the plug out and using your hand kick the engine over until no more fuel exits from the sparkplug hole.

After all this, check the gearbox oil is correct, as it could leak out while the bike is upside down, before trying to start the bike again with a clean, dry spark plug.

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