2008 YZ 250 JD Jetting? and Boyesen Rad Valve?

2 replies to this topic
  • 650RACER

Posted August 12, 2009 - 01:24 PM


Hey guys so I recently picked up an 08 YZ 250 and naturally I have a heap of parts coming for it. I ordered a JD jet kit as I have used them on all my 4 strokes over the years w/ great results. Naturally I assumed that his kit for the 2 stroke would be equally as good.

The bike I bought came w/ the Boyesen Rad Valve and I am wonderng if any of you have any experience w/ JD Jetting? Do any of you have any experience w/ the Boyesen Rad valve? I dont.

What about JD jetting and the Rad valve together?

Broad question I know but the rad valve instructions say to use 1 size leaner main and possibly pilot. I know JD's kits have a tapered needle and are set up leaner than stock already.

Any input would be great. I will post some pics when I get her finished and once I have a chance to ride her this Sunday :thumbsup:

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  • djmamayek

Posted August 12, 2009 - 01:49 PM


Rad valve is good for some mid and up power, probably lose a bit of bottom. I don't think you'll have any troubles with the JD setup and the Rad Valve. I personally have no experience with the JD Jetting, but the Rad Valve is great... I've used V-Force and Boyesen and have preffered Boyesen.

  • yathump

Posted August 12, 2009 - 03:51 PM


I'd contact JD himself just to see if he has any input in this

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