79 CB125s Throttle stuck rolled on

[Shoshin]

Started my bike this morning to ride to work, opened the choke, and the throttle started high then just escalated to full bore. Immediately knocked off the choke, no effect. Throttle control was not stuck nor would not twist down, pulling harder on the throttle escalated the revs even further.
I rode it last night and it handled perfectly, no issues (though I was riding it for the first time in a couple days after some torrential storms: it sat outside)
Only thing I could think was that I'd left the petcock open overnight ( no clue how this might effect, I'm new to bike mechanics and riding in general)
I'm sure there's a plethora of things that could cause this, but I'm confused as to how it would happen overnight.. I am worried someone might have tampered with it? (it sits in a locked gate access shared with neighbors)
Glad I still have my cage to commute in, but I'd like to address this asap, any idea where to start?

 

[DirtyFrank]

I'd bet money that you need to either untighten your throttle cable cap on the carb a bit or loosen the two nuts that hold the carb onto the intake. On this carb, it's really easy to overtighten and have the slide bind up. It has happened to me before and having the throttle stuck wide open while riding is no fun.

 

[DirtyFrank]

Any update? I'm curious.