It's the chrome colored pin sticking out of the blue bezel ring at the carb's throttle arm area... pull it out with small pliers.

You'll need to set the high speed needle first, then adjust the low speed (the low speed is most likely too rich... turn it clockwise when adjusting).

You may not think it matters a whole lot, but the low speed screw is SO SENSITIVE it will drive you crazy. Move this screw (when getting close to perfect) the width of your screwdriver's blade/slot... Yes, it's that sensitive.

To check the low speed screw: Go to full power for a few seconds, then quickly bring the throttle down to idle (make sure your throttle trim is set low enough for a good low idle). Once the throttle is down, listen to the idle... if after a 10 to 20 seconds the idle slowly goes softer and softer... your low speed setting is rich. To double check yourself here at low idle, quickly bring the throttle to full power- if it trips over itself, sputters, coughs and gags it's a sign it's rich (the spraybar has too much fuel to consume).

Make your adjustments a micro movement at a time on the low speed. Don't be discouraged if it takes you a 1/2 hour of more to do this.


One other thing that can make these adjustments null and void - air bubbles in the carb feed line from the tank. Once in a while monitor the tubing during operation for a bubble-free fuel feeding.

Good luck. you'll get it.