WR426 fouling plugs


6 replies to this topic
  • rob_wilko

Posted February 21, 2010 - 01:00 AM

#1

Gday,

I'm having trouble with my 01 WR426 fouling plugs in a very short time (less than 10 hours). But what is strange is that I haven't changed any of my setups. I believe that the cause could be a rich mix, but Ive had the same settings for the last year, and the tuning has been fine up until now.
When the bike wont start, I take the blug out, and the tip is sooty. After I clean it up, the bike starts no worries. I wouldnt be so concerned if the plus wasnt such a pain in the arse to get at.

Could it be a blocked or over oiled air filter ?

Cheers,
Wilko

  • 426 NOOB

Posted February 21, 2010 - 01:09 AM

#2

Gday,

I'm having trouble with my 01 WR426 fouling plugs in a very short time (less than 10 hours). But what is strange is that I haven't changed any of my setups. I believe that the cause could be a rich mix, but Ive had the same settings for the last year, and the tuning has been fine up until now.
When the bike wont start, I take the blug out, and the tip is sooty. After I clean it up, the bike starts no worries. I wouldnt be so concerned if the plus wasnt such a pain in the arse to get at.

Could it be a blocked or over oiled air filter ?

Cheers,
Wilko


this could be a number of things. First though is i would change the plug with a brand new one. If you have cleaned it repeatedly it may be making the problem worse and just how old is the plug in it now? If it were air filter related, it would most likely be because it was dirty (unless you just oiled it and ran the bike without letting the oil dry a bit). Also it could be ignition related. But replace the plug first.

  • 426 NOOB

Posted February 21, 2010 - 01:12 AM

#3

oh, and also, how does it run once you get it started, does it have a bog or blubber at all or does it run very crisp and clean?

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  • rob_wilko

Posted February 23, 2010 - 03:20 AM

#4

426 NOOB,
a couple of things, firstly, the i put a rand new plug in about a week ago, and it has already fouled it, secondly regarding the air filter, it wasn't REALLY dirty, but moderately dirty. However, i remembered that last time i oiled it, i didnt have any filter oil left so i used engine oil, and most likely didn't let it dry - would this be bad ?
Finally, when it does run after i have cleaned the plug, it is not as crisp as it probably should be - there are a few little backfires, bogs, and blubbers.

Thanks a lot for your help
Rob

  • rob_wilko

Posted February 23, 2010 - 03:20 AM

#5

sorry, meant to say "brand" new plug, not "rand"

  • s14 2510s

Posted February 23, 2010 - 04:35 AM

#6

I just got done doing a 3 hour ice race with my 426. I thought i was having plug problems too all year. turns out my coil wire was coming loose. came off on lap 26 and would olney pop. pushed it back to the pits and found the wire off. It runs better then it has all year.

  • g-powerr

Posted February 23, 2010 - 11:17 AM

#7

don't use engine oil for your filter! and those backfires-you're probably running too lean and need to rejet. also you can try an irridium spark plug with the combination of the light blue wire mod - i've never fouled a plug since i've done that.





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