hard to tell how big that brass fitting is from the photo
maybe the crankcase vent tube, from the top of the rear cylinder on the left side of the bike, to the air box above the carbs?
I cant see anything that looks like that on my 2005 650 - maybe its up under the gas tank where I cant see it. Maybe one of the hoses for the Air Injection System AIS, in which case the bike would not run right at all if its disconnected.
not sure what to make of your starter kicking in? maybe the starter button is somehow shorting when you twist the throttle?
try twisting the throttle with the key and kill switch on, and see if the starter engages
otherwise I would think something is wrong with the start clutch.
Last edited by KCW; 08-31-2018 at 08:07 PM.