Long range tank piping?????? WTH????

[Gooseneck1975]

Dumela
Finally got around to playing with the XR today, flushing the tanks and carbs etc

But what the hell, under the tank is a 4 outlet pipes and on the left is a some kind of vacumm assist jobie and the fuel tap on the right is higher than any of the outlets and they are all connected!!

Took the bike for a quick spin and the fule wouldnt stand still so I could see where it was going to/ from??

Can anybody explain the how and the why?

Only picture I have at the moment is attached

 

[JC]

 

[Dux]

 

[Gooseneck1975]

 

[JC]

 

[Dux]

 

[Gooseneck1975]

 

[Runner]

 

[Dux]

 

[Gooseneck1975]