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The different types of motorcycle suspension explained

Written by Francesco Di Betta | August 04, 2023

When it comes to choosing a bike, comfort is one of the key elements taken into consideration by riders.

Motorcycle suspension is the assembly which guarantees shock absorption while riding, helping the bike remain balanced – above all when braking – and offering specific comfort to the rider on the basis of its configuration.

Let’s take a closer look at the most common types of suspension on the market.

The wide world of motorcycle suspension

Motorcycle suspension was introduced in the early 20th century, and initially was only available on the front wheel.

Now we tend to identify suspension as shock absorbers too, given that this system helps the bike travel without problems on different roads, ensuring the stability of the vehicle and the safety of the rider.

Suspension systems are not all created equal, however. There are various different types:

  • Telescopic
  • Upside-down (USD) or inverted forks
  • Hydraulic spring
  • Gas-charged 
  • Mono-shock suspension

Let’s take a closer look!

Telescopic motorcycle suspension

Telescopic motorcycle suspension systems are used for the front suspension on almost all modern bikes.

A stanchion and a slider are positioned inside this suspension system to provide freedom of movement.

Inside them are a spring and oil to absorb impacts.

The main advantages are the simplicity of design and fairly economical construction.

Upside-down (USD) or inverted forks

The classification of USD forks is also known as inverted forks, and they are essentially the same design as telescopic forks.

This type of suspension places the fork tube near the axle and the external slider at the top, where it compresses for greater manoeuvrability and comfort.

The USD layout offers three main advantages: 

  • Decreases additional motorbike weight
  • Increases flexibility
  • Improves manoeuvrability/handling

Hydraulic spring motorcycle suspension

This suspension system is based on the use of a type of fluid called damping oil, located in the hydraulic piston.

On the outside is a spring which ensures that the piston, after lowering due to pressure, returns to the correct position.

Suspension systems based on damping oil have a potentially serious problem: intensive use can create air bubbles inside the damping oil which lead to cavitation, which has a negative impact on the operation of the components.

Gas charged shock absorbers 

Due precisely to the phenomenon of cavitation, hydraulic spring suspension is not sufficiently tough and reliable for long journeys. 

To solve this problem, a cylinder of gas, generally nitrogen, is added to hydraulic spring suspension systems.

The main role of this gas is to prevent the formation of bubbles inside the oil chamber, thus preventing the onset of cavitation and providing greater reliability for the bike on longer journeys.

 

 

Monoshocks

A single shock absorber connected to the rear frame of a motorbike to absorb road unevenness is known as a monoshock suspension.

It is generally positioned in front of the rear wheel and uses a linkage to connect to the swingarm. 

The benefits of this type of suspension are:

  • Better cornering
  • Ease of adjustment and tuning
  • Improved vehicle handling and smoother ride

On the other hand, maintenance is often more onerous, with an inability to withstand excessive loads translating into reduced longevity compared to other types of suspension.

If you are thinking about overhauling the suspension workstation in your workshop, put your trust in the experience of KIRO's technicians and the professional quality of our workshop furniture.

Get in touch for a free, no-obligation consultation now: