650 kms in one direction on Kawasaki 750 cc, without problems.
With People 250 S, 250 kms in one direction, two up, all the time on the highway, indicated 140-155 km/h.
When I had 50 cc, the longest trip I did was around 300 kms in one day, but I was much younger then.
Mind you, 300 kms means traveling through three states in my case (Croatia, Slovenia, Italy) and crossing corresponding number of borders.
Agility 50 is Honda Goldwing compared to what I rode at the time (Peugeot Zenith 50 cc with 10" tires
.