Need to know the flote height for a 1968 honda motorcycle 350

Hi! I presume you have a Kei Shein carburettor set up? if so there really isnt a float height as such, if you are experiencing flooding or fuel spewing out of the rear aperture it is more likely the float needle/valve is either worn or has foreign matter stopping it from shutting out the fuel supply.
When you take the float bowl off and look at the float you'll see at the end under a tang a tiny spring around the tang which is attached to the float needle careful removal will reveal all for servicing.
O.K. penny dropped? do you mean Needle Jet? if so try middle to start and check plug colour after good run, remember raising richens the mixture lowering weakens. Trial & error I'm afraid as mileage, wear and fuel quality all determine final result?
Good luck!
Paul 'W'
Onyer~EDson(:0)~[><