Henry Cole rides the Wiltshire Downs on a new BSA Goldstar, setting sets off from Royal Wootton Bassett to historic Avebury, which is famous for its Neolithic stone rings, and the market town of Marlborough. Plus, a visit to the Goodwood Festival of Speed, where there's a big surprise for bike boffin Allen Milllyard, and the restoration of a Kawasaki Z1000 from a huge box of parts.