Carburetor Cleaning & Tuning 101
ok. so i see a total of three holes under the tank..... the one that spits fuel out is the petcock...... i know what hooks up too it.. then i have two more holes.. a fat and skinny. ..so my vacuum hose connects into it????
Dissevered helped you out there - the other 2 ports coming out the bottom of your tank is for vent hoses. They just drop down so they can spit out the bottom of the bike if they need to.
what year is your bike? It's possible that you have had a diff petcock installed over the years. Sometimes the F3 petcock is installed - it's cheaper and less problematic than the F2, but you need to shut the fuel valve off on the petcock when the bike sits for a while, as it could cause flooding. (the f3 had an electric fuel pump that metered fuel flow to the carbs - the F2 used hat vacuum pulse line and a diaphragm, kinda like a chainsaw motor.)

Looks like you have a F3 petcock. In that situation you need to plug the vacuum line port, as it is not used anymore.
No - there won't be a hose from the carbs in your situation - there's nowhere on your petcock for it to connect. The skinny opening in the bottom of the tank is a vent line, so is the bigger opening. Both just will drop down and need to be positioned somewhere that they will allow fuel to flow out the bottom of the bike if you were to overfill the tank, or slosh fuel somewhere that it doesn't need to be. If you don't connect vent lines to these, it would potentially allow fuel to just spill down and pool onto the hot engine case in those situations, which I hope we all agree is a bad idea.


