To directly address his original question though, his machine ought to be able to go faster than 50 if there wasn't an incline or headwind. If it won't, even new and tight, something is a little off. This bike has been sitting quite awhile somewhere since it is a 13 with 26 miles.
If he got it new from a dealer with warranty, he should have them check the usual fuel, air and electrical points for a long term storage bike. If he has to fix it himself, we'll need more info. Pull the plugs, check the fuel flow and such.
I may not be good, but I'm slow.
2014 M70 Retros, the sports car of Urals.