2003 YZ450F Wont start

3 replies to this topic
  • writebrian

Posted October 04, 2013 - 06:48 PM


Bike has been sitting for 9/10 months. Drained all gas and replaced with fresh. Checked oil and coolant. Went through normal start procedure 2 blips on throttle, fuel on, choke out and bike started on 3 or 4 kicks and ran fine around the neighborhood for 10 minutes... after almost a year of sitting!!!


Shut down that night, came out next day and NOTHING. I have kicked it 150 times and not even trying to turn over. In desperation I had my friend tow me behind his bike today and could not bump start it in at least a 1/4 mile of towing. It seems like there is no spark at all. Not even trying to catch. 


ANy ideas on where I should start looking? Any procedures to narrow down problem? I am not a particularly mechanical guy but can try some basic stuff. 


Any help appreciated!

  • nuity5

Posted October 04, 2013 - 09:38 PM


I would start with what you mentioned in your post - spark. Pull the plug, stick it in the coil, ground the shell then kick and see if you have any spark. It could be as simple as a fouled plug. Stick another one in if you don't have any spark as it's by far the easiest and cheapest first try. I would put a plug in even if you have spark. If you have spark then move to fuel. I would at least pull the pilot jet (best to pull and clean the whole carb for inspection) and make sure everything's good. Put the carb back on and verify you have fuel out of the accelerator pump nozzle before you put the airbox boot back on. Clay

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  • writebrian

Posted October 04, 2013 - 09:46 PM


Thanks... How do I make sure the shell is grounded when I pull the plug?

  • 3d0

Posted October 05, 2013 - 01:22 AM


Thanks... How do I make sure the shell is grounded when I pull the plug?


Don't really wont to put them on any painted parts.

Lay the shell down on your engine blocks, or place it next to the cylinder. Don't touch the plug, now give her a nice smooth kick and watch for blue sparks.

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