Accelerator Pump Screw

2 replies to this topic
  • Unibomber

Posted April 03, 2004 - 03:45 PM


What does it do.
I think this is just on 03/04s The manual calls it the accelerator pump adjusting screw.

What does it do, what would adjusting it do. :)

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  • jerryls

Posted April 03, 2004 - 10:00 PM


It adjusts the squirt of fuel when you first turn the throttle. If you are bogging from idle, this is what you adjust to get rid of it (and maybe a #40 leak jet).


  • skthom2320

Posted April 04, 2004 - 02:56 PM


There are two things to consider about the squirt from the AP (1) the timing and (2) the length.

The AP screw controls the timing of when the squirt starts.

The leak jet referred to in the previous post would adjust the length of the squirt.

The timing of the squirt is very critical to having a snappy off-idle response. You can adjust it 1/4 turn at a time and use the seat of the pants method to find the best position. When it is not adjusted properly you will have a terrible bog.

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