There are three basic styles of motorcycle helmets: full-face, three quarter shell, and half shell helmets. Each style has its advantages and disadvantages, and the helmet you prefer will likely depend upon your tastes. However, to an extent, what kind of bike you ride might also determine the style you choose.
Full-face motorcycle helmets: These helmets cover the entire head and most of the face. The hard shell extends from the brow over the cranium to the base of the skull at the top of the neck. The shell rides forward along the cheekbones to encompass the jaws and chin, leaving a wrap-around view port. A clear acrylic visor slides over the view port to block out wind, rain and dust and to ease eye fatigue. Most full-face helmets are vented at the chin and within the shell. Vents normally have sliding doors for use in cold weather. The inner shell is highly padded and the helmet has a chinstrap for securing.
These helmets are considered the safest type of helmet to wear in terms of sheer protection, as they cover the widest area of the head and face. A disadvantage is that they are the heaviest of all motorcycle helmets, and as such can create the greatest neck fatigue from wind resistance. They are also the most restrictive helmets in terms of limiting sensory input.
Mainly people who own sports bikes or cafe racers, such as Kawasaki Ninjas or Honda Interceptors, wear full-face helmets. The better motorcycle helmets in this category are racing helmets, designed to be as sleek as possible, minimizing wind resistance and neck fatigue.
A lighter version of the full-face helmet is made for dirt biking. Visually, a dirt bike motorcycle helmet differs from a street helmet by the presence of a large shade bill over the view port and the absence of a visor. Dirt bike helmets are made to wear with goggles.
Three quarter shell motorcycle helmets: This style is similar to a full-face helmet, but it does not wrap around the face. The shell extends from the brow over the cranium to the base of the neck and forward over the ears. A chinstrap secures the helmet, sometimes in the form of a chin cup.
These helmets are popular with police officers, as it is easy to communicate with the helmet in place. Also, the helmet can be quickly removed without momentarily blocking the vision, unlike a full-face helmet. However, three quarter shell helmets still afford much of the same protections as full-face helmets.
For the most part, people who prefer three quarter shell helmets are those that rack up road miles on large full dress bikes, like the Harley Davidson Road King or the Honda Gold Wing. Headsets are often installed in three quarter shell motorcycle helmets and used to communicate with other riders.
Three quarter shell helmets are rarely chosen to wear on a cruiser and virtually never seen on those riding café racers.
Half shell motorcycle helmets: Often called beanie helmets, these are the least intrusive style of helmets, covering only the top half of the cranium. They weigh the least, do not block the ears, and offer the least wind resistance. They also afford the least protection.
Those that ride cruisers like Harley Davidson Softtails, FXR-series and Sportsters, or older bikes like Panheads, Knuckleheads and Shovelheads, usually wear half shell helmets. This helmet is commonly chosen by those who would not be wearing a helmet if it were not required by state law. Riders of café racers do not wear beanie helmets as they afford too little protection, and riders of touring bikes normally want more protection for the long miles they log.
To meet legal requirements for those states that have a mandatory motorcycle helmet law, all helmets must meet the DOT standard, a minimum safety standard set by the Department of Transportation (DOT). Any helmet meeting this standard is required to feature a DOT sticker.
SNELL is a non-profit organization that sets a more stringent voluntary standard. A helmet does not have to meet the SNELL standard to be street legal, but if a helmet is both DOT and SNELL approved, it is designed to meet the highest standards of protection. More protection usually means more weight, and certainly more cost.
It is important that the helmet fit properly. If it is too big for the rider, the wind will get underneath it and pull it upwards, straining the neck. If too tight, it will cause a headache. Allow an experienced dealer to help with the fit. The lighter the helmet, the less it will pull on the neck in high wind. New construction using carbon compounds has significantly lessened overall helmet weight since the older fiberglass models.
It is well known that even the safest helmets provide minimal protection in the event of a fall. Motorcycle accident statistics indicate that the best protection against injury includes a Motorcycle Safety Awareness course, defensive riding skills and a personal commitment to ride safely at all times.