How fast will a typhoon go with 172 kit?

Hi guys i have a 2003 typhoon 125 with only 5000 miles on the clock. its really starting to get on my goat as im a big fella 16 stone. the bike struggles to get me to 65 mph and if its windy 60mph is a push. i have just bought a malossi 172 kits for £200 and im going to fit it tomorrow but im going to keep everything else completely stock. i dont want to bike to go 100mph i just want a little more speed so i can overtake cars without worry. does anyone have a rough idea how fast a standard typhoon will go with a 172 kit? many thanks in advance