I had a problem like that with my 83 200x. I had broken a tooth off of one of the kicker gears. The broken piece got jammed up, then jiggled itself loose. If there is a loose piece in her motor somewhere, it could have vibrated out when the trike was bouncing on the trailer.
The other potenital is that the shifter is slightly bent, such that when she shifted, the tranny jammed. Again that could have cleared with the jiggling on the trailer.
I would keep an eye on it, and keep riding
ATCnut
82 185s - sold
83 200x (hopped up)
84 200x (stock)
84 70 (lost this one to the DMV)
85 70 (soon to have lights, a foot brake, and CDI ignition)
84 200es (parts trike) - sold
85 350X (the best)
85 350X (siezed motor, dream of a poweroll kit someday)
85 250sx (frame was trash, got parted out)
86 250sx (the tractor)
86 250sx (a nicer tractor)
86 250sx (an even nicer tractor)
87 200x (parts trike, its really rough, a dog was chewing on it for a while)
87 250es Big Red (the tank!!)