4 stroke engines how they work.& when they don't Doh!

[bez]

Need some advice, in fact most likely a lot of it. I’ve recently bought a 520sx kept up with the maintenance. But now like all bikes is causing some problems. I can start the bike, but to keep it running you have to keep the revs up. This started out of the blue 1 second it was running the next it wasn’t nothing was adjusted, not bang or cracks or falls.

I need to get as much information as possible on engines how they work how to fix them, check them, doing anything really. A dummies guide to 4 strokes would be ideal.

Any help at al would be more than appreciated

 

[KiwiBird]

Sounds like something in the carb - maybe water or a bit of dirt blocking the pilot jet. Try draining the fuel from the carb with the drain screw on the bottom of the carb and then remove the bowl drain (17mm nut on bottom). You can then blow up through the pilot and main jet from the bottom with compressed air.

If that doesn't fix it you may need to remove and disassemble the carb and blow out the passageways with compressed air.