426 running rich?

7 replies to this topic
  • bmxchamp00

Posted April 13, 2014 - 09:21 AM


My bike fouled a new spark plug in about 3 months and sometimes it is hard to start sometimes without the hot start on even though it had just been idling for about a minute. Pilot jet??

  • grayracer513

Posted April 13, 2014 - 05:05 PM


Maybe, but I had a YZ450 that was a little like that, and it was just a quirky bike that way.  But you can check the relative pilot jet size as you adjust it:



  • bmxchamp00

Posted April 16, 2014 - 05:56 AM


My 2002 426 was running perfect last week after 1k in the shop about 5 months ago, and then it started acting like it was running rich so I cleaned out the carb and checked that the pilot jet was the right size. (It is) and after putting it back together it will turn over after many kicks but not start. Any thing else I need to check? What is up with this bike??!

  • morphrider

Posted April 16, 2014 - 06:12 AM


Number 1 on the list, put a new plug in.

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  • hithebrakes

Posted April 16, 2014 - 06:21 AM


How old is the fuel have you checked the valves spark plug air filter

  • bmxchamp00

Posted April 19, 2014 - 11:46 AM


Turns out the plug was bad. I thought it was more than that. Thanks guys

  • joey330

Posted April 19, 2014 - 11:56 AM


Turns out the plug was bad. I thought it was more than that. Thanks guys

Sometimes it's the smallest little thing

  • seacraft69

Posted April 20, 2014 - 05:18 AM


Yep. Just like Slingblade

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