YZ 426 Jetting

3 replies to this topic
  • Jay_Jostrand

Posted August 17, 2000 - 06:45 AM


I live in Dallas, Texas (only a few hundred feet above sea level) and ride my 426 with the stock jetting. I'm taking a riding vacation to Cloud Croft, NM in a few weeks which is 8,500 feet above sea level. I am concerned about whether or not I will need to modify my jetting for the increase in elevation. Does anyone have any experience with these types of elevation changes or successful jetting changes?

  • fershy

Posted August 17, 2000 - 07:49 AM


drop one main, raise the needle clip and dial in the PJ needle. Or read the many posts regarding high altitude jetting.

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  • Hick

Posted August 18, 2000 - 06:16 AM



I have ridden in the Ruidoso area (about 30 miles north) recently and ran the exact jetting Fershy described but I also went one leaner on the pilot. That's probably not a big deal though.

In the summer you may even go two sizes leaner on the main...

But I've also ran the stock jetting at this altitude and it didn't run too bad at all, but I fouled a plug while warming it up.

I have never ridden in the Cloudcroft area, but it is less than a two hour drive for me so I would really appreciate some trail tips when you get back from your ride. Send me an email when you get the chance.


  • Gary_Kessler

Posted August 18, 2000 - 06:49 PM


Hey Jay - tell us how the riding is at Croftcloud when you get back! Pictures?!?

'00 WR; YZ modified, DSP exhaust system, UNI air, Dunlop D756, ProTapers, Devol Rad Guards, P-38, Mason/Dean Jetting specs. . .and lovin' it!

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