All I would say on the subject is make sure your GB license covers you for riding the bike, ie cc, if you do not have a full license (motor bike) you can only ride a bike up to 50cc on a full car license, and then only for a specific time without taking a CBT test in the uk, a lot of accidents last year by tourist were not covered on there insurance because they were riding bikes they had no license for ie over 50cc.