Newb. I need some guidence.

2 replies to this topic
  • jsonic

Posted June 03, 2012 - 03:30 PM


Whats up guys and gals. I just bought a 08 450f. When i brought her home i changed the oil, made sure coolent level was good, and all that stuff. When i checked the plug i noticed it was kinda whitish and i know that means its running lean. it backfires a little when i let off the gas and It does have an open exhaust. im 100% sure it wasnt rejetted. Im also a lil on the heavier side weighing in at a 205 lbs. and i believe the suspension has never been setup. My question is how do i rejet this bike and setup my suspension for my weight. ALSO! i had a fork seal leak in my left front fork, and i thought for sure i needed to replace the seal. but i did a lil trick that can save you time and money lol. its called the seal mate. Look it up on youtube. I made my tool out of a notebook cover and it fixed my leak. I was extremely happy lol. But yeah. anyone know how to rejet and setup a suspension? :-)

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  • DBOBYZ450

Posted June 06, 2012 - 12:40 AM


Congrats on the bike, im sure youll fall in love with your 450 like the rest of us, for you suspension and your jetting issues, go to the sticky threads at the top of our yz 450 section. same place you just posted at.

good luck

  • grayracer513

Posted June 06, 2012 - 05:35 AM


The whitish plug DOES NOT indicate a lean condition. Using plug color to gauge jetting is only useful and reasonably accurate when the engine is run hard and then cut off and coasted to a stop before reading the plug, AND while using leaded fuel. It was the lead that produced the color, and since the introduction of unleaded fuels, the only thing the plug will tell you is whether the heat range is right or not. Whitish plugs are normal. Don't fall for 50 year old myths.

Also, if the pilot (idle) circuit is correctly adjusted, it SHOULD backfire "a little" on decel. Not always, not a lot, but some.

Check out the fuel system section of the Common Threads sticky.

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