dumb question LOOK HERE

2 replies to this topic

Posted January 10, 2005 - 12:19 PM


Well ever since this cold weather came around here in SoCal my bike has been backfiring. The bike runs great but every time i start it up on the stand and rev it the motor backfires once or twice. I have put the JD jet kit in it and a Zipty fuel screw, the fuel screw is out about 1 1/4 turns. I was wondering if maybe its running too lean but in this cold weather shouldnt the bike need to run leaner because before in the summer in never backfired and now all of a sudden this weather comes along and its acting up. Anyway I have a 170 main jet in it and the blue needle on the 3rd clip poisition from top. Please help

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

Posted January 10, 2005 - 12:40 PM


As the weather turns colder, the mixture will become more lean (the colder the air, the more dense, therefore there will be a higher air to fuel ratio). You need to adjust your fuel screw. These bikes are sensitive to temperature changes. Add more fuel to the mix (turn the fuel screw out at 1/4 turn intervals, and you'll find your right mixture again).


Posted January 10, 2005 - 12:45 PM


Ok ill try that, thanx for the info, i just figured that colder meant leaner but then again these dam four strokes are so complicated.
thank you again.

Related Content

WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 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

The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  113 replies

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • * * * * *
  • 1 review
  • Last review by Tommyk_55
  • On January 15, 2017

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 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.