Carb Jet ?

Alfalfa said:

well i took it apart again and the slow jet (#38 but manual says should be #80) looks like it is clogged half way down. I tried running some wire through it to clear it up but that stuff is stuck in there good. So then I filed a nail down to fit inside the jet and still the damn thing won't go through. Also it looks like there is some kind of brass plug where there should be a hole in the pilot jet here is a pick. Should I just buy a new slow jet and pilot jet?

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The Honda CB500T manual is wrong in this case - slow and pilot jets range from 35 to 40, 38 being the most commonly seen.
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???

Normally I avoid poking anything down in a jet, the brass can damage pretty easily.
When I feel I have to, I use a piece of old guitar string, which I always have in abundance, and can be very thin.

As Steve has pointed out before, jet sizes refer to the orifice diameter in mm - meaning a 130 is 1.3 mm, 38 would be 0.38 mm, etc.
That's a pretty small opening.

All that really matters on a jet is the orifice size - I think the slow jet may be bigger-to-smaller to provide sort of a reservoir - since it's not fed directly from the float chamber, but has a couple of right angles to go through, it may be a necessary design feature.
Just guessing about that, but ol' Man Honda generally knew what he was doing.

I have a couple of spare 450 carbs around, if you decide you want to replace the slow jets.

If it will only run with the choke partly applied (not sure what you mean by on/off) then it's a lean condition. Could be caused by plugged jets, too small jets, sticky slides, a variety of reasons.