Congratulation and excellent purchase. You will be very happy with your new scooter. I should know, I have one 
On a public road, mine only goes 50km/h (53km/h really with the GPS, reading 62km/h on the speedo), but that is just due to Australian law. On a closed road or a track, it will do 84km/h indicated on the flat and 91km/h on a slight hill.
The only things that I have done to it for track use is removed the ring restrictor in the transmission and disabled the rev sensor wire on the CDI unit. I have been informed that there maybe an air-flow restrictor in the air box but I am yet to have a look for that. Other mods due will be a pipe for sure and maybe a malossi variator.
But bang for bucks, it is surely a winner straight out of the box. ScooterHQ are pretty clued up on parts for the R50X, so you might want to drop them a line for parts.