missing vac line on fuel press regulater 2000 monster 900

[k7gsxr1000duc]

i just purchased a 2000 monster 900 ,it has a aftermarket pipe and k an n filter w top of air box cut open . I pulled air box off to do some cleaning down under it and noticed there is no small line hooked to the fuel press regulater and cant find any extra line laying anywhere that should be hooked to it . is there a reason for this that im not aware of .i have been into bikes for years but this is my first Ducati .

[ducpainter]

Welcome.

That small nipple is just a vent to atmosphere and requires no hose.

[Duck-Stew]

No hose goes on there as delivered.  Not for venting, but I did try hooking up a vac line and although I didn't check for a difference in fuel pressure, the bike rode the same with or without it hooked up  (1999 SS750i.e.).

[krista]

It's probably for turbos to alter the fuel pressure with boost. It's likely those regulators were the easiest to source when Ducati put that efi design together.

Yes, I am avoiding work today...

[Bill in OKC]

I had a 1997 Moto Guzzi 1100i sport and that vacuum port was connected to the intake vacuum.  I *think* maybe to increase fuel pressure when there was more throttle opening or something.  It was basically a car system adapted to a bike.  I disconnected the line once to see if it made any difference and I couldn't tell anything different.