Some Motorcycles have an on-board, in built Immobiliser system straight from the manufacturer. Not all of these systems are Thatcham Approved, for whatever reason. To find out which motorcycles are approved, click on the Thatcham web site at http://www.thatcham.org/security/pdfs/categories/MotorcyclesCAT2.pdf to see if your motorcycle is listed there. If it isn't, your motorcycle does NOT have an insurance approved Category 2 immobiliser and you will need a Category 1 (known as CAT1) system. If it is listed, you will only need an Acumen CAT21(Category 2:1) system to take the motorcycle to a full CAT1 status. Some Insurers will require you to have a CAT1 system. Some will be happy with teh CAT2 Immobiliser, but you may still wish to upgarde with the Acumen CAT21 or even a budget alarm such as the Acumen CAT3.1