Attached is a photo comparison with a Kokesh float and a float of normal buoyancy.
The extinct Kokesh brass float was the heaviest of all floats ever produced, averageing four times more than any original Linkert (or Schebler DLX) float.
(Competitor's brass floats that often suffered leakage weighed only three times as much. They were NOT made in China, but India, as if that makes the slightest difference, as if from Detroit or Indianapolis.)
A float is supposed to float. Duh.
Any compromise sacrifices performance and fuel mileage:
The purpose of a bowl is to supply a reserve for accelleration among other things.
The limits were found quite early, and that is why flat-trackers often enlarged their bowls, as illustrated at http://beautyofspeed.com/gallery/linkert/linkert.htm
Reserve is WHY you have a bowl.
Brass floats were greatly enlarged in an attempt to gain buoyancy at the expense or buoyancy.
Setting your float to 3/8" (or more accurately for a 12g Kokesh .410") robs you of just that much more reserve.
Fuel mileage is robbed by the sluggish inertia of a heavy float.
The amplitude of the wave of shutting off and opening up is greatly magnified, leaving the motor operating under longer periods that are over-rich, or over-lean.
Your motor craves a steady-state, with a very low amplitude of change: a sensitive float.
Langsenkamp and Linkert never
produced a brass float for a Model M carb, because it would be futile.
On to the Rubber Ducky and other "similar" materials, ... THEY ARE NOT ALL SIMILAR!
Beware of off-patent obsolete "Nitrophyll" floats that are imposters,
and beware that the current lull in USA fuel digestivity may be temporary.
And if-and-when your "similar" float swells, please consider whether your source can replace it with anything better.
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