Harley Davidson Rich Idle, Black Smoke, Petcock Vacuum Leaking Raw fuel
Not a permanent fix, only if you are stranded on side of road from cheap vacuum operated shut off valve. Taiyo Giken vacuum operated petcock seal failed allowing fuel to bypass carb via vacuum port and over rich engine while running. Temporarily converting petcock to eliminate troublesome vacuum valve.
If your eyes burn and bike won’t idle then see if gas come out of your petcock vacuum line when vacuum is applied...