10.6 drops of LaTromba T per valve applied holding the completely dry valve at 30°. Spin the piston once in the casing at 6 RPM before tightening up the valve caps.
This only works on Mondays, Thursdays, Saturdays and Sundays. My valves are never dirty or stick on the other days.
Typical valve casing/pistons really belong in the dumb invention department. There is no forced lubrication and with very few exceptions, the valve geometry does not match that of the hand, there is a cursed hole on the bottom end cap that keeps dry cleaners in business!
The only way to correctly oil, is to remove the piston and end caps, swab the casing until it is clean and dry, do the same to the pistons, then oil and reinsert. You need to use enough that the whole piston has a thin film over it. It everything must be dry as oil floats on water - no protection!
Due to the stupid design, it doesn't matter if you use too much oil, the excess drips onto your pants through the hole in the end cap.