We might be talking about two different screws, Greg. See the bottom of Page 21 of the Honda GXV120-160 Owner's Manual:

[Linked Image]

Here is the full Owner's Manual:

http://engines.honda.com/pdf/manuals/31ZE6030.pdf

Here is the same instruction from Page 6 of the GXV140 Owner's Manual:

[Linked Image]

Here is the complete GXV140 Owner's Manual:

http://engines.honda.com/pdf/manuals/31ZG9642.pdf

The screw Mark has replaced with a plated UNC screw, sets the idle speed, as shown in the Owner's Manual. In Honda's terminology it is correctly called the throttle stop screw, as you said.

Last edited by grumpy; 06/11/12 07:32 AM. Reason: Add detail