When I first got into the carburetor-adjusting game, air/fuel mixers had their pilot screws located on their flanks, right in front of—and within reach of—God and everyone else. All you had to do to adjust a carb's pilot screw was just reach on over and give it a twist. For a number of good reasons, the majority of motorcycle carburetor pilot screws have now migrated to the carburetor's underside, which may make a lot of sense from a machining and airflow perspective, but it complicates their adjustment.
Over the years I've cobbled up a number of Rube Goldberg devices to do the job, but none of them have worked very well, so after years of screwing around (literally) I finally went out and scored myself a Motion Pro Pilot Screw Adjusting Tool.
The Motion Pro tool is a thin, 17-inch-long right-angle screwdriver that turns within a fixed tube. The one-inch-deep throat allows it to clear the deepest float bowl so you can reach into formerly inaccessible spots and adjust the pilot screw with ease. Well-made and well-thought-out, the tool also incorporates a collar that positions it against the screw seat, holding it in place, and an adjustable stop that sets the bit's depth, preventing it from skipping out of the pilot screw when torque is applied.
My only gripe is the lack of datum marks on the handle. Consequently, my addled old brain kept losing count of how many turns I'd put on the screws, but a permanent marker took care of that.
Bottom line? The Motion Pro Part no. 08-00119 Pilot Screw Adjusting Tool is a tool I'd spend my own money on. In fact, I did, and the $29.40 was well spent. If you have never checked out Motion Pro's line of motorcycle specialty tools, you owe it to yourself to do so.
For additional evaluations of, comparisons of, and shopping advice for motorcycle gear and accessories, see the Accessories and Gear section of MotorcycleCruiser.com.