The floats have been changed from the brass type to the plastic type. I don't run overflow tubes on these carbs but perhaps I should. I'll take the float bowl off again and have a better look at the brass vent pipe. I'll check the float tang and valve pin again but as I mentioned earlier the fuel stops flowing properly when the float rises.
I'll try the clear tube procedure for measuring the correct float height. I can't remember the height for measuring with the bowl on. Does anyone have a reference or a link? I didn't see it in the stock manual.
There's a hint.
Here's a couple things about the unique early carbs (type "A"):
1. They tend to build up a small ridge on the sideposts (where the pin mounts the float pivot to the carb) with the lighter brass floats because the floats bobble quite a bit in use.
2. Since your floats are plastic, they need to be set slightly differently (spelled "leaner") from the brass floats. specifically, the plastic floats must be set to 26mm depth from the surface of the notch in the outisde of the float gasket surface, not from the tiny sliver of a tab inside the float gasket's surface. Those little sliver reference posts are only for use with the brass floats, which ride higher in the fuel than the plastic ones.
If you set the plastic floats at the normal staggered 25 and 26mm for the K1 "A" series carbs, they fill up to 1mm below the level of the overflow tube, so they frequently dribble. This was why Honda switched to the plastic-floated "B" series carbs in the New Factory bikes. By the later K2 all of them had the plastic floats. Of course, the brass floats reappeared briefly in the fabled 086a carbs and F0 bikes, but they dribbled, too, and went away. In hard acceleration and lots of frame motion (like racing and dragracing) the brass floats promote a deeper average float bowl depth than do the plastic ones, so they were often favored by those guys 'in the day'. On the street (like mine) you can expect occasional dribbles.
