What is an illegal driver?
For individuals who play golf at a purely social level, there are very few restrictions on the types of clubs that can be used. In particular, many social golfers buy golf drivers who are considered illegal for use in some amateur and professional events. Different managing bodies in the golf world have different regulations for what represents an illegal driver, and publishes an illegal list of drivers to avoid confusion. Several manufacturers will make these illegal drivers accessible to the general public, although it is forbidden to use drivers in official competitions.
Common factors that make an illegal driver unusable during the official competition include the face of a club that has a high restitution coefficient (COR), violates certain depth requirements, or uses the club's face or shafts that have been banned. For example, some golf associations prohibit the use of an illegal driver who has any opening towards the back of the club. The reason for this determinedIt is that open design changes the weight and aerodynamics of the club's face and provides an unfair advantage to those who use it. Another variation of this rule, forced by certain associations, states that the club head cannot have more cavities towards the back of the club.
Most golf associations are interested in equal conditions that ensure fair competition between golf amateurs and professionals. Like the requirement for the shape of the club, some organizations prohibit high KOR drivers. This attribute usually increases the elasticity of the club, which means that when the driver's face hits the ball, the reaction is more elastic and more power is applied to the ball. The result is an increase in drive distance, which is clearly advantageous for individuals using this particular driver.
Another common factor that causes a certain golf from illegal is the shape of the front of the club face. Many golf associations have minimal requirements for ÚHel faces of the club. If the face is perfectly flat, the golfer may have an advantage because its units will usually be more straight. There are other similar attributes of club faces that could suppress the shortcomings of the golfers, and would therefore provide an unfair advantage over the competition. For example, many management bodies prohibit the use of drivers who have club faces over a certain size, weight or volume.
Although less common, another attribute that has resulted in some drivers on the list of illegal drivers is the shaft composition. Most manufacturers use steel or graphite shafts, but some groups prohibit the use of other materials or composites. Similarly, some groups do not allow the club core to contain certain materials. Many drivers have titanium, wooden or steel cores, and some associations do not allow the use of any other materials.