Pulled my carbs off tonight

[XSive Okie]

After much research on here, I finally pulled my carbs. It went much smoother than anticipated. Only took me 30 minutes or less. Now tomorrow night I will start the "triple clean", check float heights, make sure jets are correct sizes, and bench and vacuum synch. Hopefully I will find something that is the cause of my mid-range stumble, and bring my MPG's up where the rest of you guys are. I'm only getting around 12, and running very rich, even with multiple vacuum synchings. Oh, and I'm going to recoat the carb holder boots with some Plasti-dip while everything is apart. And I'm happy to report non of the idle screw are broken off!

[foreda]

Floats n jets

My bet is float height.

[XSive Okie]

You're probably right, Foreda

My line of thinking was that or wrong pilot jets. All will be checked thorughly.

[foreda]

Jets

My line of thinking was that or wrong pilot jets. All will be checked thorughly.

It is quite possible that it could be both. This is why I only use Mikuni oem jets.
If you are using brass floats,make sure you check for leaks.

[petejw]

also check for any blockages in the 2 vent tubes
that go to the air box,
and i think the 79 had adj needles, u mite want to
check on the position of the clips. jat

[DGXSER]

HERE is a great guide I have found for tuning these carbs.

I would look at the needle clip position. It makes a huge difference. On the 81 carbs, the needle is not adjustable, however, I installed it wrong on one carb my first time through these. that one carb was rich as rich could be until the mains kicked in. Would foul out the plug at low end.

[XSive Okie]

What I found out

Insides looked pretty clean, sprayed everything out, checked jet sizes (all good), slide boots not torn, needle clips in position #3, sprayed some more, checked float levels, not all good. Carb #4 was set VERY rich, but 1-3 measured out fine. Could one carb make enough trouble for the way the whole machine runs? Mid range pops, stumbles, and surging are the symptoms she is exhibiting. Low-end and top-end run great (alot of black smoke under WOT though). Still need to coat intake boots and then I will re-assemble and see if I get a change. Hoping so!