I think Roger's carb is a Model HD11, from a late-60s Electra Glide. The sportster carbs were model HD2A thru D as I recall. The Sportster carbs had the idle adjust thumbwheel on the top and an accelerator pump molded into the plastic diaphragm cover. The Glide's carb had the idle adjust on the side and a plain stamped domed cover for the diaphragm with a vent hole in the middle. That vent hole looks to be where Roger installed the tube tapping the intake pressure. Tillotson's "HD" model designation does not refer to Harley Davidson specifically, as the HD11 carbs were used on various snowmobiles too.
Chris On 10/13/2015 6:40 AM, Roger Bulla via KRnet wrote: > Also, I see from the HD carb (as on the 1960s Harley Sportsters) > exploded view that the idle adjustment screw is on top of the carb. > How do you get to it with your setup? Looks tight ;o) > > -Oscar > > > Oscar > > On this particular HD the idle mixture screw is on the lower left > side of the carb as you are sitting in the plane. The main mixture > screw is on the right. It seems as with many carburetors, there were a > lot of variances depending on the application. > > Roger
