93' Nighthawk Issue

[nxer88]

I have a 1993 Nighthawk 750. The bike runs great and always has. Starts right away and never stalls out or anything. The problem I’m having is that after a ride, the bike stinks of gasoline. Even while riding, sometimes I can smell strong gasoline odors. Opening the gas tank after an extended ride, I hear a slight woosh. Recently, I removed the carbs to have them cleaned and found gasoline in the airbox. Obviously, the gas tank is not venting properly.

1. Carbs have been professionally cleaned and rebuilt.
2. Petcock is brand new.
3. Vacuum hose and fuel line hoses are brand new.
4. The bike always starts and runs great.
5. The gas tank is not original, but I believe the bike was having the same issue with the original gas tank.

Anything I’m missing here? Honestly, if it weren’t for the smell of gasoline, I wouldn’t even know there was a problem. I included a photo of each of my Nighthawks. This issue is with the red one - the black one is perfectly fine and always has been.

 

[VintageDad]

No vent in the tank. Long ride, tank heats up, gas expands filling the carbs.

 

[slmjim n Z1BEBE]

Check / clean the vent in the tank's cap, that it's clear to vent to atmosphere. Requires some disassembly. If you try doing it with the cap on the tank, tape over the opening in the tank so small dropped parts don't fall in.

Good Ridin'
slmjim & Z1BEBE