Road legal quad bikes are off-road vehicles that have been retrofitted or manufactured to be ridden legally on the road in traffic. Most quad bikes are not street legal; they are designed exclusively for off-road riding and do not feature many of the safety components necessary to make a vehicle safe for on-road riding. Street legal quad bikes often feature stop lights, rear view mirrors, and tires that fit certain specifications for on-road use. Road legal quad bikes must also be a certain size to be considered road legal; requirements for making a quad bike road legal will vary from location to location, so it is necessary to check with local laws before operating such a vehicle on the road.
In most places, road legal quad bikes must be registered like any other on-road vehicle before it can be driven on the road. Owners will need to register the vehicle and often prove that the vehicle has been made to be road legal. In some places, the owner might also be required to procure automobile insurance for the vehicle before registering it. Such insurance is usually quite inexpensive, as are the fees for registering street legal quad bikes, but fees can vary significantly from location to location.
The quad bike will need to be modified to include safety features and to meet certain road specifications. The tires of the vehicle may need to be changed to a road-friendly version that will allow adequate steering capabilities while on pavement. Tires with an excessively aggressive tread may not be allowed on-road because they can alter steering capabilities. Road legal quad bikes will also need to feature both front and rear lights, brake lights, and turn signals similar to the ones found on automobiles. These lights are meant to indicate the rider's intent in traffic and to indicate when the rider is coming to a full stop.
Rear view mirrors will also be necessary to make the quad bike road legal. The mirrors allow the operator to see vehicles behind him during lane changes and other road maneuvers. Some locations require the quad to feature just one rear view mirror, while other locations will require the operator to install two mirrors, one on each side of the handlebar. Other requirements will vary by location; some places require that the quad feature enclosed wheel wells and foot wells to protect the rider from road debris.