Confirm fuel and air lines

Hey guys,

I've got the original manuals, but I was hoping to confirm with someone the name, use and positions of the following tubes and lines:

Ok so from the gas tank, fuel flows through the filters into the fuelcocks and then out the bottom into the two tubes and through the inline fuel filter.

Then the fuel filter attaches to the clear skinny tube that runs into the carbs (second photo). That completes the main fuel supply.

That leaves my breather and vacuum tubes (the two black tubes hanging off the sides of the engine) and a larger diameter clear tube that runs into the top of the engine, ahead of the carbs. Can someone tell me if the breather and vacuum tubes attach to anything? And can someone identify that larger diameter clear tube?

Bike was dropped off on my doorstep so it's a partial rebuild. Any help would be appreciated!

Your petcocks are vacuum powered. They won't flow fuel without a vacuum line attached. The two vacuum lines from your intake manifolds attach to the small nipples on those plates on the back of the petcocks. The large diameter clear tube is the engine breather hose. Originally, it connected to the airbox so any oil vapors emitted got recycled through the engine. With no airbox, you can simply vent the line to atmosphere, add a little filter to the end if you like, or add a power brake check valve. The check valve set-up is what many of us prefer. It lets air out but not back in. This can create a slight vacuum in the crankcases which helps prevent oil leaks and is also supposed to benefit performance.

5twins!! That is exactly what I needed - Thx!

Neat tip with the Power Brake valve. Makes sense.