Does anyone know if there's a replacement petrol cap for these bikes? I know touratech do one but the price is insane and it doesn't even lock. I figure the pattern must fit some other bike but I've ruled out the other F and G650s. I know it was built in the Italian Aprilia factory but it certainly doesn't match to the Pegaso because the contemporary model had an electronic release. Is there anything else with the same hole pattern? Ideally I'd like to fit a locking aircraft style cap so there's no piece to remove.