Basically you will need to check your licence to see if it as Category 'A' on it. 

Where do you look for it? On both types of licence, the old paper type or the new photo licences paper counterpart it is in a small boxed off area marked 'PROVISIONAL ENTITLEMENT' you will need to have the category 'A' motorcycle endorsement with the expiry date based on your 70th birth date.

If you do not have this endorsement or the date has passed, please contact the DVLA to have it re instated.