Easy, assuming it's only 5 (my top 5 in a top 10 would all be Triumphs and no. 6 would be a Norton) and on the basis that I'd be content riding any one of them every day.
Rocket, Street Triple, Tiger 1050, Ducati Diavel, Yamaha XJR 1300.
As long as money is no object, I'll assume I'm 30 years younger as well. Current new production only as including vintage bikes would take forever to decide.
Had to wheel and MV Brutale out of the workshop the other day. Thing weighed about as much as your average 250. Really surprised me how light it was. If only I could sit on a bike like that for more than 10 minutes.