GSX1100 has me stumped

[playswithnitro]

I need ideas...

GSX1100 16v
Stock CV carbs and airbox.
Had stock ignition. Now completely swapped for Dyna-S with coils and leads. Relay supplying (measured) 12V
Valve clearances at 8-thou on both sides. EFE grind on GSX sticks.

Starts and idles very well. Free revs very freely. Pulls hard through mid-range. Above 5-6000 it goes very rich. Spitting out black smoke.
Almost seems to shut down and refire but doesn't backfire.

Was doing this with stock ignition. Have stripped and cleaned carbs.

Mains are 112.5. Air/fuel drops to low 9s on dyno. Tried various mains including 90s but no real change.

HELP!

[dr_fosg8]

Float height incorrectly set. Possibly a bad fuel tap, I believe that you should have a vacuum operated petcock. If the diaphram inside the petcock is bad it will allow fuel to flow down the vacuum line into carb #2 causing a rich condition in that cylinder.

[hampshirehog]

What throttle position does it play silly buggers at?

[isleoman]

Are you running a KN style air filter? Have you recently recoated it? If you put too much goop on it ccould create those symptoms.

[chef1366]

Is your charging system and battery good?

[rapidray]

Valve clearances are too loose also. Should be more like .004-.006 at the most. Ray

[playswithnitro]

Thank you all.

The problem was very simple... Somebody had removed the rubber plugs from the pilot jets and not replaced them. Fitting four small pieces of rubber cured it instantly.

Bike is now running like a good thing but needs suspension work next.

[rapidray]

You still need to re-adjust the valves to the correct specs. Ray.

[playswithnitro]

Thank you Ray. I'll get on that first thing tomorrow.

[tom203]

Thank you all.

The problem was very simple... Somebody had removed the rubber plugs from the pilot jets and not replaced them. Fitting four small pieces of rubber cured it instantly.

Bike is now running like a good thing but needs suspension work next.

Wow, those little jets not being semi-blocked off made it run rich enough for black smoke in mid range-surprising; thanks for update.