nope...bummer
To answer my own question...no it is not adjustable. I took it apart - it is vacume operated and appears to require a needle change to adjust. Access is by taking off the tank - remove 2 phillips screws on top of carb - remove lid and spring, remove rubber, plastic unit. pull needle retainer out (white plastic tab inside) and slide needle out. There is only one clip position with a plastic spacer and metal washer. Maybe different spacers can be used to adjust.