Fouled Plug

5 replies to this topic
  • stathy1

Posted January 02, 2006 - 07:43 PM


I just bought my son a 2005 yz85 and he is just learning to ride the new
bike and is not riding it too hard and is having a problem of fouling the plug.
What can anybody suggest i do to stop this from hapening.Should i turn in the pilot air screw adustment to lean it out a little? Or any other suggestions.
Other than that the bike runs great.I am also mixing the fuel at 36 to 1

  • BigIvyI

Posted January 02, 2006 - 07:50 PM


try dropping the main jet one size at a time.

  • stathy1

Posted January 02, 2006 - 07:55 PM


you don't think i sould change the pilot air screw?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • jct404

Posted January 02, 2006 - 08:01 PM


My boy's 65 was similar and I dropped the needle one notch, you may even go a size smaller on the idle jet too. If he isn't opening it up you need to cut back on the fuel. 0 to half throttle is mainly your air fuel screw, slow idle jet and your needle position in the main jet in that sequence. Dropping the needle and adjusting the air/fuel screw cost $0.00.

  • stathy1

Posted January 02, 2006 - 08:09 PM


I'm not quite sure how to drop the needle at this time so do you think ajusting the pilot air screw alone will help?

  • jct404

Posted January 02, 2006 - 08:33 PM


Not really, The owners manual should have a step by step description on how to do it. It not too bad especially on the smaller bikes.

Related Content


Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.