00 YZ426 No Spark

4 replies to this topic
  • elise111

Posted October 13, 2004 - 11:11 AM


Just bought a YZ supermoto. During my maiden voyage the bike started fine, I rode for less than 3 miles and the bike cut-out under heavy acceleration in 2nd gear. This was my first time laying into the throttle. It did not spudder like it was running out of gas, it just quit. Would not restart, even with bump starting going down hill. My findings after looking at the bike last night:

-Not fuel- tank was half full, I've confirmed fuel is in the float bowl
-No spark- pulled the tank, pulled the plug, turned headlight/kill switch on, grounded plug on case, cranked. No spark, even in a dark room to look for a faint spark
-Not the plug- tried another plug from a working engine, again no spark
-Not the headlight/kill switch-no continuity when on and continuity when off- checks okay
-Likely not the coil- resistance pretty close to spec (over by 2 ohms), so I think this is okay
-Not the stator windings- all three windings check okay for resistance
-Checked neutral switch- does not go to ground in neutral like it should, but I've read that this is not a problem, the bike should start with no neutral switch.

The only thing remaining on my list is the CDI unit itself or perhaps the coil since it was slightly out of spec. Am I missing anything? Seems odd for these components to fail this way. Any ideas? Thanks.

  • Fastest1

Posted October 13, 2004 - 03:07 PM


Have you checked all of the connections? If nothing checks out, I do have an extra CDI box for a 2000 (I am running a Wolf/Vortex set up). I would let it go cheap. Good Luck
Dont forget to check to see if the kill switch shorted. :cry: Just unplug it and see if she starts. :cry:

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  • Satch0922

Posted October 13, 2004 - 04:41 PM


Kill switch.

HEY JOHN...we missed you this weekend!!

  • elise111

Posted October 14, 2004 - 07:10 AM


Thanks for your advice, guys. While the kill switch (headlight switch in my case) checked out okay, it appears that the dual sport wiring was incorrectly tee'd into this circuit. I'm sparking again!

  • Fastest1

Posted October 14, 2004 - 09:29 AM


:cry: Nothing like fixing it at home! :cry:

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