The Honda CB500T manual is wrong in this case - slow and pilot jets range from 35 to 40, 38 being the most commonly seen.Alfalfa said:
Main jet anywhere from 140 to 150.
There is no jet in the carb that's 80 size.
What is identified as a "pilot" jet actually is a plug, there is no hole in it, at least from the top (or end that hangs down in the float bowl, with the number stamped on it) - that's why you can't seem to clear it out. The pencil points to it in the photo.
The photos are actually of a 450 carb, but they're the same as 500T, except for the goofy "air cut valve".
The "slow" jet lies underneath this, screwed in the little tube or cavity (arrow #1).
It receives its fuel from a tiny passage that is connected to the main jet cavity (arrow #2).
It's a bit difficult to see from the photo, but if you pull it apart you can see the little passageway.
Arrow #3 points to a little brass sealing ball, pressed into the opening that was used to drill out the little passageway.
Does this help???