Where should my jetting be at?

7 replies to this topic
  • Zakrad_u

Posted December 27, 2011 - 04:12 PM


1200 ft, stock header, 4.1 slip on. and want jets for about 50-60 degrees..


EDIT: I also have a slight bog when stabbing the throttle. Is this from the AP? how can I adjust it.

  • Zakrad_u

Posted December 27, 2011 - 07:20 PM



  • grayracer513

Posted December 27, 2011 - 08:35 PM


Check out the jetting DB sticky at the top of the index for this forum for suggestions.

As for the bog, you first need to learn not to "stab" the throttle, but "roll" it instead. It's a four-stroke skill. You don't need to open the throttle more slowly, really, just more smoothly. If it still stumbles, then you may need to work over your pilot circuit, needle size, or accelerator pump.

Setting the pump timing is covered in the manual.

  • Zakrad_u

Posted December 27, 2011 - 08:38 PM


Well, what is the stock pilot? and i was thinkinh of going to a 165 main.

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  • grayracer513

Posted December 27, 2011 - 08:41 PM


You haven't looked at the sticky yet, have you? Post 6 in the '09 thread lists the stock jetting, as does the manual.


  • Zakrad_u

Posted December 27, 2011 - 08:44 PM


Yes I have, few times actually. But it was too much help since everyone in that thread was either like my set up but diff elevation or same elevation and a full system so I'm not sure where to go. Probably will go 48 pilot 165 main since its winter now.

  • Zakrad_u

Posted December 28, 2011 - 08:30 AM



  • Krannie McKranface

Posted December 28, 2011 - 05:03 PM


The stock jetting is fine your your altitude and temp.

Adjusting the acclerator pump is THE thing to getting throttle response.

It's easy:

- Lift up the subframe (remove exhaust can)
- with motor off, roll the throttle on and watch the stream of gas leave the apump nozzle.
- it should never hit the slide
- now WACK it wide open: it should shoot all the way into the head no problem, for 1 sec.
- if the stream hits the slide, turn the adjustment screw under the cover on the right side clockwise.
- if the stream never hits the slide, turn it out a half turn to see if it's too late, or if it then hits the slide, turn it back in.

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