A bike forks main purpose is to hold the front wheel of the bike while at the same time allowing the rider to balance and steer. Choosing bike forks depends on a number of different factors such as whether suspension forks are required, how big the forks need to be and which material should be used. For example, many bike forks are made from a combination of materials including aluminum, steel and carbon fiber.

A bike fork consists of several parts. There are two “blades” which join together at the crown, the steering tube from which the handlebars are attached and the dropouts which are used to hold the wheel in position.

Sizing

There are a number of different measurements used for bike forks. Here are a few of the most important that you need to consider when looking at bike forks for sale.

The length of a bike fork is measured from the lower section of the lower bearing to the axle of the front wheel. The width of the fork is measured from between the edge of the two dropouts. Often this is around 10cm although downhill mountain bike forks have a slightly bigger width.

Other measurements include the offset, steer tube length and diameter. The offset is how much the dropouts curve outwards from the line of the steering tube. The steerer tube length is important as it defines the height o the headset.

Suspension Forks

Suspension forks are most commonly seen on mountain bikes where the need for shock absorption while riding on rough terrain is important. Suspension bike forks usually contain a set of “legs” or telescoping tubes. The upper tube can move inside the lower tube in order to provide a level of suspension. Suspension forks usually include a spring and a dashpot (sometimes known as a damper). There are a number of different types of spring including compressed air and elastomer. As you’d expect, the type of spring used has a major effect on the way the fork reacts to different situations. Compressed air is one of the lighter choices.

Which type of bike suspension forks you should buy depends on which type of biking you plan on doing. There are forks for downhill, cross country and free ride biking. Racing suspension forks tend to the lightest and hence most likely to break.

Rigid Forks

Rigid forks are more commonly used on road bikes where maximum power to the wheels is more important than shock absorption. The shape and weight of rigid forks has a greater effect on the handling and feel of a bike than with suspension forks. For racing bike forks carbon fiber is often used because it is a light, strong material that has a certain level of shock absorption without requiring true suspension.

Brands

Although there are many brands who manufacture bike forks some of the most famous include Fox, Marzocchi and Onza. Fox and Marzocchi primarily produce mountain bike suspension forks. Onza are known for producing both rigid and suspension forks – especially for trial bikes.