From Jonathon McEvoy, [Daily] Mail Online, 22/6/2014. “Lewis Hamilton has set himself the target of emulating Britain’s John Surtees, the only man to win world championships on two and four wheels. Surtees, who is now 80, added the Formula One title of 1966 to seven motorcycle world championships – an accomplishment that not only won him the BBC Sports Personality of the Year award but motor-sport immortality. After watching the Catalunya MotoGP race in Barcelona a week ago, Hamilton said: ‘It’s a great sport and it’s good that the fans can get so close to the action.’ ‘I have had a passion for motorbikes since I was a young boy. I always asked my dad for a bike but he said no. He thought they were too dangerous, and he bought me a go-kart instead.’ ‘I really want to try MotoGP one day. John Surtees won a world title on a bike and in a car, so it would be cool to do that, too.’ ‘It’s easy to be popped off a bike, though, so you couldn’t take the risk during an F1 season. But I’ll definitely try it one day.’ Hamilton owns a MV Agusta – a make of bike ridden to world championship success by Surtees He has spoken before of being star-struck meeting the six-time MotoGP champion Valentino Rossi, the most celebrated rider of the modern era. He was similarly impressed by watching Marc Marquez, the young Spanish sensation of the track, in Barcelona last week. ‘The charisma and personality Marc has when you’re watching on TV was exactly the same when I met him,’ said Hamilton, 29. ‘I was overwhelmed.’ ‘Marquez has won seven races in a row. That’s inspired me, left me thinking, “Jeez, I’d like to do that”. That’s my goal now.’ ‘I see some reflections of myself in Marc.’”                                                                                                                                                                             

Schumacher tried bikes at club level but never took it any further i believe                                                                                                                                                                              

He rode a Ducati in the German national championship (IDM) in 2008, ninjaflump. Well spotted.  
                                                                                                                                                                             

And Damon Hill was a race winning bike racer before moving to F1!