If you are currently running at a sprint track, in Formula 80 Senior (2004 IKF National Class #5), the most likely road race crossover classes are...
 
 

IKF National Class #18 - Formula 80 Senior

 
Rule Differences...
 

Brakes:
 

Front brakes are optional.
 

Tires:
 

No compound or manufacturer restrictions.  5" rim diameter maximum.
 

Intake:
 

Air filter may be used, in place of an air box, unless local authority mandates differently.
 

Exhaust:
 

Silencer body minimun of 2.5" diameter and 8" length.
 

Race / Heats:
 

20 minute heats.
 

NCK Local Option Class #28 - West Coast 80cc Sprint

 
Rule Differences...
 

Weight:
 

380 lbs.
 

Brakes:
 

Front brakes are optional.
 

Tires:
 

No compound or manufacturer restrictions.  5" rim diameter maximum.
 

Intake:
 

Air filter may be used, in place of an air box, unless local authority mandates differently.
 

Exhaust:
 

Silencer body minimun of 2.5" diameter and 8" length.
 

Race / Heats:
 

30 minute race.