650cc. This BSA Rocket Gold Star has recently been part of a deceased estate. It was built in 1957 and later imported into the UK, where it was first registered on 1st May 1991. There are no receipts with the bike, but it comes with an an old BSA Owners Club handbook and the current V5C indicating 9 former keepers in the UK. It has been re-commissioned, and the vendor tells us it rides well. The odometer displays 180 miles. Not specified