"The 33 bhp category disappears in the EU from January as more age related restrictions come in, but there will now be a 47 bhp intermediate licence category."
The Harley 883cc Sportster and the 400cc Ninja have about 45 peak horsepower- maybe the UK rule makers looked at these 2 bikes.
My Honda 600cc cruiser has about 33 peak horsepower with a custom exhaust and rejetting, giving it about the same top speed as a 250cc Ninja, but it is slower in corners because it weighs more and scrapes the footpegs sooner, with its lower seat and frame.
“Do…not waste time protesting the self-inflated showmen and bloviating bullshitters who populate our culture. It’s more fun to marvel at them, to appreciate them, to be grateful for them, and to mock them relentlessly. ”-from the 2010 book American Freak Show by Willie Geist. "He wondered what difference any of it would make two hundred years from now." -from the book Cyclops by Clive Cussler.