JDjetting kit received - no info on what settings for a free flow exhaust?


8 replies to this topic
  • MTS II

Posted June 11, 2009 - 06:23 PM

#1

I was under the impression the kit would have a setting for stock exhaust setup and one for a free flow. I have a Yosh pipe/header setup - pipe has spark arrestor - should i just use the only setting that JD included?

Also - are most YZ426 owners running the thick or thin o-ring? My bike is an '02.

Thanks

  • biwwy2000

Posted June 11, 2009 - 07:38 PM

#2

just call jd

they are great and will help you out with any question.
they have seen it all.

using the o ring results in less delay between throttle movement and ap activation.
the thicker o ring has a qricker response than the thinner one.
some riders don't even use and o ring and just use bailing wire for instant response.

i use the thicker o ring for quick response but with some give.



biwwy

  • MTS II

Posted June 11, 2009 - 08:41 PM

#3

Went ahead and did the install with the 170, blue needle in the 4 position, thicker o-ring.

Turns out this bike had an o-ring on it at somepoint - I found it when installing the new one. The old one was split in half. Testing this out on Sat.

  • grayracer513

Posted June 11, 2009 - 09:40 PM

#4

What makes you think that the stock 426 pipe is not a free flowing exhaust? Or that the Yosh is that different? There is likely to be very little difference, if any, in the ideal jetting for either pipe.

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  • MTS II

Posted June 12, 2009 - 07:10 AM

#5

What makes you think that the stock 426 pipe is not a free flowing exhaust? Or that the Yosh is that different? There is likely to be very little difference, if any, in the ideal jetting for either pipe.


Was told that information by a few people. I went with the stock JD setup after reading a couple more threads here that there is not much difference.

  • grayracer513

Posted June 12, 2009 - 07:56 AM

#6

Look this one over, too.

http://www.thumperta...699#post2881699

  • Diode663

Posted June 12, 2009 - 09:40 AM

#7

Correct me if Im wrong, but isnt the blue needle for cold weather?

  • DND

Posted June 12, 2009 - 03:10 PM

#8

Correct me if Im wrong, but isnt the blue needle for cold weather?


You are correct. JD's instructions say to use the Blue needle for conditions below 50F.

  • 642MX

Posted June 12, 2009 - 03:31 PM

#9

I've had the best luck with the red needle... I'd also throw the o-ring in the trash, they break in a short period of time. I wired mine. :thumbsup:





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