Stranded Roadside

On my way home from work today bike started accelerating spontaneously. First time it happened I thought I had imagined it. I shifted gears and braked and it snapped back into line. It happened again. And then it happened over and over with increasing frequency and ferocity. Finally, it reached 8k on the tachometer, even with no hand on the throttle. The tach would not drop below 8k even with no throttle applied at all.

Idle adjustment is not the issue ... The idle stop is well out of the way. I pulled over to inspect. Throttle action (push and pull cables) is fine. Nothing obviously broken or out of place on throttle/carb mechanisms. I'm sitting by the side of the road waiting for My Harley Babe (tm) to come pick me up with the rescue trailer.

Humiliating!!! But not worth damage to bike or self to ride the remaining three miles home. All it needs to do is add another 2k to its idle speed and I'll be hitting the rev limiter. I don't feel like burning up the clutch today with 8k startups.

Any thoughts on WTF?

Any ideas on roadside adjustments that might allow That Redhaired Bitch (tm) a.k.a. Jezebel to return home on her own power.

Thanks in advance.