Mountain Bike Category System Explained -------------------------------------------------------------------------------- What AGE category do I race in? All categories in MTB racing are age based until you get to the age of 19. To work out which category you belong in, see the table below. As an example, if you are 14 now, but have a birthday later in the year, then you are classed as a 15 year old and would race in the Youth category: Juvenile - To qualify for the Juvenile category, a rider must be at least 12 years old or be in their 13th or 14th year. Youth - Riders in their 15th and 16th years Junior - Riders in their 17th and 18th years Senior / Expert / Elite - When a rider reaches his or her 19th year then the Senior or Sport category is the appropriate aged based category until they are in their 29th year. See below for how riders can attain Expert or Elite status. Master - for riders aged 30 to 39. Veteran - for riders aged 40 to 49. Grand Veteran - for riders aged over 50.