Q: Can an off-road class III ATV Dirt Bike be made street legal?
A: Some dirt bikes can be made street legal, some can not.
First Step: Contact the manufacturer (not the dealership) of the motorcycle, such as Honda or Yamaha, and find out if the engine has been certified through the US Environmental Protection Agency (EPA) to meet emission standards for use on the street. If the engine has not been certified for street use, you cannot make the motorcycle street legal. If the engine has been certified for street use, it may need a carburetor or exhaust update, as some dirt bike engines don't have the same carburetor or exhaust that the street bike conversion has. Get a letter from the manufacturer stating the engine does meet street standards and what modification, if any, it needs to meet the street use standards.
Second Step: If the engine does meet street standards, get a letter from the manufacturer listing the modifications needed to bring the motorcycle up to street standards. Such as lighting equipment (includes all lights, turn signals, reflectors, high/low beam indicator), speedometer, rear view mirror, rims, tires, exhaust, etc. These are referred to as the Federal Motor Vehicle Safety Standards (FMVSS).
Third Step: Keep all receipts for modifications. You will need the manufacturers' certificate of origin, a receipt of ownership (bill of sale), and all your receipts for modifications, plus the two letters mentioned above from the manufacturer.
Fourth Step: Take all the information to your local DMV field office when you go to register the motorcycle. You may wish to call first to see if they want to visually inspect the vehicle for a vehicle identification number (VIN) at the time you go to register the vehicle.
As stated above, some off-road dirt bikes cannot be made street legal because the engine does not meet the US EPA emission standards for street use.