Hi, I've attached a photo of my airbox on the zxr250a. Unsure what this hose piece does? It comes out the opposite side to the fuel intake, and fits nicely onto the airbox. But whether I have it on or not I can't tell the difference.
I imagine it must be, I'll have a look in the manual. I got it idling today with factory specs, excluding pilot screws which is turned 3 times out. Rode alright, definitely in need of a sync. Heard a funny pop noise when I was out though and the bike slowly died. Got it running again but unsure what that noise was.