Pre 68 bikes are limited to 1967 or earlier models. All major components must be period correct.
Pre 72 class is limited to short travel bikes and 1971 or earlier models. The rule of thumb being 7" max front wheel travel and 4" max rear wheel travel. Some model bikes in this era were shipped with rear suspension that slightly exceeds 4" rear travel. As long as these bikes are raced in "as shipped" configuration, they are legal in the pre 72 class. Bikes with modified suspension will be bumped into the EVO1 class or DQ'd. All major components must be period correct.
Pre 75 class is limited to short travel bikes and 1974 or earlier models. The rule of thumb being 7" max front wheel travel and 4" max rear wheel travel. Some model bikes in this era were shipped with rear suspension that slightly exceeds 4" rear travel. As long as these bikes are raced in "as shipped" configuration, they are legal in the pre 75 class. Bikes with modified suspension will be bumped into the EVO1 class or DQ'd. All major components must be period correct.
EVO1 bikes are limited to 1977 or earlier models. No suspension travel limits are imposed.
EVO2 bikes are limited to air cooled bikes with drum brakes and non-linkage style rear suspension. No year or model limitations imposed.
EVO3 bikes are limited to those models that came stock with (and still use) drum brakes. Water cooling and linkage rear suspension are legal in EVO 3. No year or model limitations imposed.
EVO4 bikes are 1989 or earlier models. (2-stroke 500 machines that were eventually discontinued by the major manufacturers are allowed in this class since they really didn't change much beyond 1989. Examples would be CR500, KX500, and YZ490.)
Decade bikes are ten years old and older.
Modern Support bikes can be brand spankin’ new.
Pre 77 XR75 bikes are stock or modified XR75’s that are 1976 or older.
Pre 85 XR75 bikes are stock or modified XR75’s that are 1984 or older.
Age classes (+30, +40, +50) are fairly self-explanatory. Older riders can enter younger age classes. Younger riders can not ride in older age classes. To eliminate any confusion, the age classes break down like this: +30 = 30 ~ 39 +40 = 40 ~ 49 +50 = 50 and older
It is not normal practice for ARX to have a technical inspection of bikes prior to competition. ARX reserves the right to impose technical inspection (including post race inspection) if blatant rules bending is evident.
