I did a top speed run with the 15t front in early March when it was still quite cold out. It would not pull redline and I topped out at an honest 95mph. It took quite a bit of time to get there. The big snowmobile suit I was wearing was no help. Maybe with racing leathers I could hit 100mph. I don't know. I never did a top speed run with the 14t for comparison, so the test was kinda meaningless. I'm enjoying the bike more and more. I stay off the highways and freeways because the engine feels strained at highway speeds. It's not comfortable there and neither am I. 55mph and lower is the bike's forte. I use it as a grocery-getter and do very little recreational riding. Since groceries are 15 miles away now (I moved to Rigby) the miles pile up and my average mpg is heading toward 90. I need to find an area with a longer riding season, though.