Long shot but has anyone got any idea what this is. Looks like a watch but no markings on it anywhere. Two buttons on the side push in but nothing else happens. Great looking watch band.
I used a piece of 1/8" vacuum hose. Placed one end at the edge of each carb. successively, in the exact same place & listened to the hissing sound & adjusted them to sound the same.
I soon worked out that you need to use the same ear!