A Brief Study on Motorcycle Suspension System
A motorcycle suspension system is such a system which absorbs the bumps and suspense for giving comfort of riders by absorbing the vibrations. It also provides good handling and contributes for breaking.
Types of suspension of Motorbike:
Normally motorbike has two type of suspension
- One pair of fork tube for front suspension
- Either one or two shock absorber with spring as rear suspension
Less trail means less stability, which means a quicker-steering bike. This makes these bikes a lot less stable to ride in a straight line, but a lot more flickable in the corners.
More rake means more trail, which means more stability, which makes the bike harder to turn. However, bikes with more rake work better in a straight line, which is why bikes to be long-distance cruisers use it. For example the difference between a flickable Yamaha R1 race bike and a BMW K1200LT cruiser is 24° and 26.8°
Front Suspension (Telescopic Forks)
Motorcycles today use mainly use telescopic forks for the front suspension. The forks consists of large hydraulic shock absorbers with internal coil springs. They allow the front wheel suspense up and down giving a comfortable ride.The bottom of the forks are connected to the front axle around which the front wheel spins. On typical telescopic forks, the upper portion, known as the fork tubes, slide inside the fork bodies, which are the lower part of the forks. The fork tubes must be made smooth in order to seal the fork oil inside the fork.
“Upside-down” forks, also known as inverted forks, are installed inverted compared to conventional telescopic forks. The slider bodies are at the top, fixed with the handle bar and the at the bottom, fixed to the axle.
This arrangement has two advantages:
(i) It decreases the unsprung weight of the motorcycle
(ii) It improve handling.
Two disadvantages of USD forks are:
(i) They are more expensive than conventional telescopic forks;
(ii) They are liable to lose all their damping oil if oil seal is broken
Two types to Rear Suspension
Twin-shock, regular swingarm
An H-shaped swingarm is pivoted at the front to the motorbike frame. On either side there are basic coil spring units which provide the suspension. The shocks are inside the coil spring units. This style of suspension began to fall out of favor due to weight considerations. It was also not a particularly robust design It all got a bit bendy and flexible under extreme riding conditions, and the only way to make it stronger was to add more metal, which added more weight and cost.
Monoshock Regular swingarm
Monoshock is actually a Yamaha trademark, the Honda version is called Pro-Link. This was designed to reduce some weight by redesigning the rear suspension and removing one of the coilspring units. On the current monoshock designs, there is now a linkage at the bottom end which joins the coilover to the swingarm itself. It provides less weight and hence more speed.
How can I tell my motorcycle suspension system is bad?
- The bike is lower to the ground then is was previously.
- Leakage of fluid from the shock
- Makes noises
- No damping
- Broking parts
- Change in handling