FWIW, the Bing manual states:
1. Tilt carburettor past horizontal approximately 15 degrees or an amount causing float pointer to "lightly touch" float needle spring-plunger (or ball) without depressing plunger into needle.
2. Increase or decrease pointer-to-hinge angle with a thin blade screwdriver until top surface of float element is parallel with base of carburettor. Both plastic elements must also be parallel with each other; if not, carefully twist elements to obtain correct parallelism (excessive twisting force can separate plastic from metal hinges).
3. Repeat above steps 1 and 2 until desired results are obtained.
But then, who would follow the Bing manual; where's the fun in that? YMMV.