MOTORCYCLE SUSPENSION SETUP AND YOU
July 20, 2020
Understanding motorcycle suspension is important if you wish to get the most out of your bike.
To ensure your bike is stable and each ride is comfortable it is crucial to know how to adjust the motorcycle’s suspension to your personal height and weight
ITS ALL ABOUT THE SETUP
Before you proceed w/ Bike maintenance or suspension adjustment
READ THE OWNERS MANUAL.
Its key not to assume your bike is set up correct, you still need to check it and adjust where appropriate. It a good idea to set the bike up roughly for your style for riding and weight, you can then play around with it slightly on the day of riding different terrain.
The hydraulic shock absorbers used on the rear suspensions of motorcycles are essentially the same as those used in other vehicle applications.
Motorcycle shocks do differ slightly in that they nearly always use a coil-over spring. In other words, the spring for the rear suspension is a coil spring that is installed over, or around, the shock.
In terms of adjustment, rear shocks span the range from no adjustments whatsoever to pre-load adjustments only to racing shocks with adjustments for length, pre-load, and four different kinds of damping.
SHOCK ABSORBERS
On a motorcycle with a single shock absorber rear suspension, a single shock absorber connects the rear swingarm to the motorcycle's frame. Typically, this lone shock absorber is in front of the rear wheel, and uses a linkage to connect to the swing arm. Such linkages are frequently designed to give a rising rate of damping for the rear.
BASIC TERMS ABOUT SUSPENSION
Preloading involves compressing the springs to reduce the level of play in the springs. The more you compress the spring, the less distance the suspension has to travel. Therefore, when the compression of the spring is increased, the amount of travel the suspension has to travel when the suspension takes on the weight of the car will be reduced.
Preload adjuster affects the shock/spring by either SHORTENING or EXTENDING the spring.
Pre-load
When you increase preload, the bike will rise on its suspension.
When you decrease preload, the bike will be closer to the bottom of its suspension level
Preload for the front of the bike is at the top of the fork tube. The large nut is a preload adjuster and the small nut is a rebound adjuster
When you slide fork tubes HIGHER or LOWER, it will alter front RIDE HEIGHT and CENTRE OF GRAVITY.
To change rear preload, adjust the collar on top of the spring by turning it in the respected direction.
Compression Damping
Compression damping is the function of suspension that allows a bike to ABSORB the impact of any obstacles on the road primarily potholes and speed breakers. dampingdamping
When you ride over a speed bump, the compression damping will determine the speed at which the suspension will compress.
If compression damping is stiff, the shock will be UNABLE to compress sufficiently in response to impact!
If compression damping is too loose(soft) the suspension will be compressed TOO MUCH by the bikes weight transfer as you ride over obstacles.
Rebound damping is the function of suspension that helps a bike resume its proper position after riding over an obstacle.
rebound damping controls the rate at which the spring returns to its original length after being compressed. Without rebound damping, the spring will re-extend too quickly, sometimes even further than its starting length, that causes oscillations
Too little rebound damping (Front)
The forks feel exceptionally plush when riding straight up. The bike does not want to stabilize after countersteering it quickly into corners
As you flick the bike into a corner, the front tire starts to chatter and lose traction. You feel the front as unstable through the handlebar.
Too much rebound damping (Front)
The suspension “packs down,” resulting in lack of traction especially on bumpy roads.
Ride feels harsh, opposite of too little rebound.
Too little rebound damping (Rear)
The ride is extra comfortable when cruising but starts to wallow and weave when encountering bumps.
Poor traction over bumps under hard acceleration and the wheel starts to chatter.
Too much rebound damping (Rear)
Suspension compliance becomes poor hence feels vague.
Traction is poor over bumps under hard acceleration.
GET LOW
Ride Height
The height of your bike bike’s frame and subframe are critical to the overall performance of the bike.
Less height in front will reduce rake and make the bike STEERS FASTER - THIS would also comprise the stability of the bike.
If you heighten the bike in front and bring down the back, the bike will become MORE STABLE - THIS leads to slow steering response
To adjust the ride height setting at the rear, turn the adjustable devise under the shock absorber
To adjust ride height at the front , adjust the triple-clamp forks.
UPSIDE-DOWN FORKS(USD)
"Upside-down" (USD) forks, also known as inverted forks, are installed inverted compared to conventional telescopic forks. The slider bodies are at the top, fixed in the triple clamps, and the stanchion tubes are at the bottom, fixed to the axle.
This USD arrangement has two advantages:
it decreases the unsprung weight of the motorcycle
it increases torsional stiffness, which can improve handling.
Two disadvantages of USD forks are
they are more expensive than conventional telescopic forks
they are liable to lose all their damping oil should an oil seal fail.
USD forks are typically found on sportbikes,
The basic motorcycle swingarm is a quadrilateral, with one short side connected to the motorcycle's frame with bearings so that it can pivot.[13] The other short side is the rear axle around which the rear wheel turns. The long sides are connected to the motorcycle's frame or rear sub-frame with one or two shocks with coil-over springs.
In production motorcycles, swingarms are not exactly rectangular, but their function can be more easily understood by thinking of them as such.
