Sava Fjoll 4.0, size. M/17"

The bike's suspension is designed to absorb shock and improve bike control on uneven terrain. Different types of suspension include front forks and rear shock absorbers. They can be designed with different technologies such as air, spring or oil suspension. Suspension is common on mountain bikes, while road and trekking bikes usually do not have suspension.

Fork lift refers to the amount of movement that the fork can absorb. Stroke is usually measured in millimetres and different types of wheels require different amounts of travel. Mountain bikes, such as downhill and enduro, usually use more travel, while road bikes and cross-country bikes usually use less travel.

The lockable suspension allows the rider to lock the bike's suspension, which can be advantageous on smooth surfaces where suspension is not needed. Lockable forks and shocks usually include a switch that allows the suspension to be locked and unlocked quickly and easily.

The headset is an important part of the bike that allows the handlebars and fork to rotate relative to the frame. The headset must be strong and work smoothly for the bike to function properly. There are several types of headsets, including integrated, semi-integrated, external and more.

The cassette is the part of the wheel that is attached to the rear hub and contains various gears or wheels that allow different speeds. The size and number of derailleurs in the cassette affects the range of speeds the wheel is capable of. Cassettes can be made from a variety of materials including steel, aluminium and titanium.

The hubs are the central part of the wheels that hold the spokes and allow the wheel to rotate on its axis. Hubs can be equipped with different features such as quick-release or fixed axle systems, and can be made of different materials such as aluminium or carbon.

The stem is the component that connects the handlebar to the fork. Spacers come in different lengths and angles that affect the position of the handlebars and thus the rider's position on the bike. Extensions can be made from a variety of materials, including aluminum and carbon, and can have different attachment methods such as traditional clamps or more modern tool-less systems.

The derailleur is the component on the bike that moves the chain between the sprockets on the front sprocket in a controlled manner. This allows the rider to change gear ratios and thus influence the effort required for pedalling. Shifters can be activated mechanically by cables or electronically in more advanced shifting systems.

The centre compound is an important element of the wheel that allows the pedals to turn. It is located in the central part of the frame where the pedals are attached. The centre compound must be load resistant and well sealed to resist dust and moisture. There are different types of center folders, including cartridge, hub, external and others.