A motorcycle suspension system is required on all bikes – from offroad to street motorcycles. The suspension works to make our rides more comfy. We take a look at old saddle springs, modern hydraulic dampers, and everything in between.
Motorcycle Suspension Introduction
Older motorcycles with no back suspension were also known as hard tails and could only rely on the damping of the tire and possibly the coils in the saddle. It didn’t take long before manufacturers realized the importance of motorcycle suspension, which ushered in a design revolution.
Suspension influences the driving characteristics of your motorcycle just as much as the frame or engine. The first motorcycles had a rudimentary suspension system – only the front wheel had springer suspension.
Front and rear suspensions work basically the same way. A coil spring absorbs the shock and is controlled by a hydraulic damper. This allows for compression and decompression, but prevents a catapult effect that would shoot you off the motorcycle. Oil is pressed through holes of different sizes in the shock absorber thus controlling the effect of the damping. Oil gets hot, which means some motorcycles have external oil holders so the oil can cool quicker.
Upside down motorcycle suspension is being used in motorcycles today because of the strength it gives in comparison the regular suspension setup. On a regular motorcycle suspension setup the widest part of the fork is found towards the bottom. Which in effect means that the narrow part is holding the wheel. By turning the suspension around the widest part is now closer to the frame, providing more stability and power to the whole suspension setup.
There is an alternative to the common fork suspension that is a whole different setup to the front steering of the bike. The main reason another option is being tried is because the front suspension is under the influence of braking power, resulting in a forward/backward movement that fork suspensions can’t deal with in an optimal way. However, the alternative way of steering and linking the front wheel is expensive and complicated.
Motorcycle Suspension Buying Advice
A motorcycle suspension that is too hard can really ruin a good ride. And, if you’re bottoming-out during turns and bumps, you’re going to be just as uncomfortable. Make sure you have just the right suspension for your motorcycle and that you replace it when it starts to lose its ability to recover from a jolt.
Being able to change your motorcycle’s suspension setting while you ride is a great feature on some motorcycles. Others you have to adjust before you leave. Either way, this option can really make a difference in your riding comfort when you can anticipate changing road conditions.
Ever have trouble reaching the ground?
Switching out your motorcycle suspension is a quick way to solve that problem. Your suspension determines your ride height and adjusting it even a little bit can make your bike much more comfortable to ride.
Air motorcycle suspension systems give you a smooth, reliable ride all the time. This is because they use air pressure from an onboard compressor to create lift from a twin-piston air-cylinder package. Air is also supplied on the opposite side of the sealed pistons.
Monoshock design is the single-sided swingarm that looks best on sports and endurance motorcycles. The advantage of a single-sided system is that the wheel can easily be taken out and replaced.
Twin motorcycle shocks are the old style suspension system. The classic H-shaped swingarm pivoted at the front to the motorcycle frame is considered too heavy these days. Newer shock materials are stronger and preferable to the old twin shocks that tend to get a bit bendy and flexible in extreme conditions.
Off-road motorcycles depend a lot more on their shocks than (for example) a cruiser would. So be certain you get a shock that can handle the way you ride your motorcycle.
Motorcycle Suspension Tips
- A spring’s ability to absorb bumps is expressed in pounds per inch (where about 100 pounds / inch is normal). So, 100 pound impact moves the spring 1 inch.
- There are two different types of springs:
- straight rated – the spring rate stays the same as the spring compresses
- progressive rated – the spring rate increases as the spring compresses
- A pre-loaded spring can be adjusted so it will start its first compression at a later point than normal – the motorcycle will feel a little stiffer to ride.
- Suspension tuning – your motorcycle rides very tough, any bump feels very hard and you notice it in the handling – you might have too stiff springs and damping set.
- Suspension tuning – your motorcycle rides wide in a corner as you feel the bike compressing more and more – your rebound damping is too big and springs might be too soft.
- Dealing with suspension and settings you must remember that tires, bearings, and even your frame play a part in how the motorcycle handles compression.
- Using a strap around the front shock can easily help you in measuring your sag and suspension.
- Sag should normally be 1/3 of your total suspension travel. Remember that the distance from rider height to full suspension is your suspension travel. The distance from rider height to full extension is your sag.
- Setting rebound damping is best done in small controlled steps (clicks) from a zero position. As you adjust and ride, you’ll find the perfect setting for yourself.
- When considering an aftermarket product for your motorcycle, try to replace the springs first and only later (if needed) any damping specs.
- Stiction is when fork tubes are not aligned together because of incorrect fork seals, bad settings, or even damaged fork legs.