82 750 leaking gas from airbox hose

[Nessism]

So you don't recommend doing a new float valve needle and seat, just the orings?

I would inspect the float valves first. If the needle is worn, or if the spring is too weak to hold up the float, replace them. Keyster and real Mikuni float valves are by far the best. You will need float bowl gaskets, typically, and maybe the rubber pilot plugs. I often buy these kits for the float valves and gaskets. Add a full O-ring kit, because the rebuild kits O-rings don't fill out what's needed.

https://www.siriusconinc.com/products/detail/601

[tom203]

https://www.georgefixs.com

[longranger44]

Well finally got the new petcock on, while I had the tank off I checked the valve clearances and put in a new gasket for the cover. The old one was leaking and all of the bolts were loose, some backed off several turns. Took hours to clean all down in the spark plug valleys but got it done, hopefully that will solve my smoking problem. Side note, I learned that if you want to clean baked on crusty old oil, berrymans b12 cuts through it like butter. Super noxious though.

Anyway with the new petcock the issue is gone, it's running normally again. I'll fill the tank tonight and ride a bit and see if it stays that way. Eventually I'll pull the carbs and do o rings and clean everything but I'll probably make that a winter project as it tentatively seems to be running fine now. Thanks for all the replies and links!