poor spark!!!!

3 replies to this topic
  • marktt31

Posted October 25, 2005 - 01:23 PM


(YZ426- 2002 model)
I have poor starting problems when the bike as been stalled or dropped and also on odd occasions when cold, i know this is common with the 426 but i have to replace the spark plug every few rides because the spark seems very weak and will not start at all but as soon as a new pug is put in BRRRMMMM, it has been fitted with lights for trail riding and i,m not sure what stator is in it (how do i identify it) could it be the original YZ stator or would it have to have been replaced because when i use it at night you have to keep the revs up or the light fades out. Is there a connection here!!! , plus what gap should be between the pick up and the flywheel as it is adjustable and there is no mention in my manual.
Regards Mark
I have shimmed up the cams and recut valves and replaced piston recently but has made no difference to starting when hot.

  • Emiliano

Posted October 28, 2005 - 12:29 PM


I really don´t know much in this case because of the ligths, but for sure the plug must work for al least 6/8 month

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  • phat_450f

Posted October 28, 2005 - 01:20 PM


yeah I had a 00 426 and i would only change the plug once every season. I think you are getting warm on the matter of the stator. I am not a electrician though....Possilbly there is a trouble shooting guide that lets you know how much electricity should be going to that wire...Get the specs on that and see what you get...

  • henrysdad

Posted October 29, 2005 - 03:23 PM


I had the same problem. Based on your description of how your lights worked.I'll say you have the 45 watt Electrex stator. It looks similar to stock ,but has a yellow wire.

The one I had burnt out on the ignition side.
Replace it or forget lights and get a stock stator assembly.

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