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Suspension Setup


It will be difficult to set up your bike in one day unless you wish to spend a lot of time in the saddle. Therefore, I have split up this article into different days to make it easier to read and carry out. Click on a link to jump to a portion of the article.

DAY 1 - What is “suspension” all about?
Your bike suspension is designed primarily to absorb the imperfections in the roads, and ensure that the tires keep contact with the road. Most motorcycle suspensions are based on a spring (similar to one you would find in a pen, or mattress, but much stronger) as well as 3 oil shocks. To stop the spring from bouncing the tire; the speed at which the spring moves up and down is controlled by “dampers”.

Dampers are like "oil filled bicycle pumps”. The pump will move faster or slower depending on the size of the hole the oil is being pumped through and also the thickness of the oil. Most bikes have both a spring and dampers. The rear wheel will have spring on the outside of the damper, named a 'rear shock'. The front suspension has the springs within the dampers, they are named 'front forks'.

The front wheel suspension is independent from the back wheel and can/will react differently to road and riding conditions.

Where do you start?
It is crucial to set up your bike in the correct order!! The steps are spelled out below. Adjusting the suspension in order will save you time and patience, ensure a more accurate setup, while providing a postive experience! Before you touch your bike, locate the handbook as supplied by the manufacturer. The handbook contains details on what can be adjusted and where on the bike the knobs and screws are for each front and rear suspension. It also details the manufacturers recommended suspension settings for your bike. If you have an aftermarket (third party) suspension, contact them for more information on setup and recommendations. Depending on your bike you may be able adjust some, or all of the following:

Note that compression and rebound are part of the damping function.

After you had establish which items you can adjust on your bike and how to adjust it, GRAB A PEN AND PAPER AND WRITE DOWN YOUR BIKES CURRENT SETTINGS, SO THAT YOU CAN RETURN THE BIKE TO NORMAL IF YOU MAKE THINGS WORSE!!! This means counting “clicks” as you turn the screws for the compression and rebound damping. Preload is easier to note and record as you can see which “notch” the rear spring is set at and which “ring” the front is on.

The manufacturer has spent a lot of time and money on research and development. Suspension is your 'connection' to the road and they take great pride in ensuring your bike handles well, therefore the manufacturers recommended suspension settings for your bike will be set up for the average rider. If you are clueless and don't want to fuss with your suspension, the manufacturer's settings are a great place to start for the average 'weekend warrior' or average rider. Compare what your current settings are for your bike against the manufacturers setting. If they are different, and things currently don't feel right, use the 'manufacturers recommended settings' to be safe..

You should be able to fiddle with your suspension and bring it back to the settings recommended by the manufacturer or your original setting before you go any further. Do not read any further unless you are competent with the above, and acknowledge that this whole article is purely for information only. You are responsible for everything that happens to YOUR bike.

 

 

DAY 2 - SET UP YOUR BIKE ACCORDING TO YOUR WEIGHT (PRELOAD/SAG)
To set up your bike you will need proper tools as recommended in your bikes handbook, usually a long screw driver (usually a flat head), 'spanner' for the front, a funny looking tool for the rear preload, and tape measurer. Most bikes will have a small tool box under the seat containing every tool necessary for any job needed on your bikel. You will need patience and time. It is best to set the bike up where you are most likely to use it, i.e. on the roads or race track. Ensure your bike is in good working condition, including replacing leaky fork seals, lubricating linkage, changing fork or shock oil, and making sure you have correct tire pressure . If you are unsure of your tyre pressure and it is a track bike use 32psi front, 30psi rear. Check your handbook or the side-wall of your tire or your individual tires specifications.

Twiddling with settings randomly or doing something half-ass will not get you far and could end up ruining your day!!! If you can't invest the time and patience, do not adjust your suspension. Suspensions can be broken down into the following categories:

If your bike does not have some of these features, then you will have to make due with the functionallity of your bike or buy aftermarket suspension. It is crucial to set up your bike in the correct order. It is best to start with front and rear Preload (Sag), as this is based on your weight and relatively easy to set up, then work your way down.

Rear Preload
Whatever your weight, when you sit on the bike, you want the bike to 'squat' just a little bit, (about 30mm) but not too much. You want to ensure that the bulk of your rear suspension travel is available for when you actually ride the bike as opposed to supporting your heavy frame.  At the same time, you should have a little bit of sag left over. If the bike drops too much, increase preload. If you are slender and pretty light, and the bike barely moves under your weight, then soften/decrease preload.
Below is a more detailed explanation. This is easy to set up but can be a bit confusing so just follow the steps one at a time.

Step 1

Step 2

Step 3

Step 1: First find the fully UNLOADED length of your rear suspension by lifting the rear wheel so that there is no weight (including the weight of the bike) on the rear axle and wheel. Measure the distance between the rear axle and a fixed point directly above the axel such as a bolt or mark on the side fairing. Note this measure measurement. Do not use a rear wheel bike stand as there is still the weight of the bike on the swing arm.
Step 2: Find the NORMAL length of you rear suspension. This is amount the suspension drops under the weigh of the bike alone without the rider. Put the bike on level ground and bounce it up and down to free any stickiness. Measure between the same two points as above, the rear axle and the fixed point you chose directly above the axel.
Step 3: Find the fully LOADED length of your rear suspension. This is the length of the suspension with the rear wheel on level ground and the rider seated on it in his normal riding position in full riding gear. First bounce up and down on the seat to loosen the suspension then get into your normal riding position with all weight on the bike and both feet on the bike. To prevent yourself from falling of (if you have not already) lean the bike against a wall and get your mate to measure between the same two points as above i.e. rear axle and the fixed point you chose directly above the axel.

A couple of terms you will need to understand: “Static sag” and “Rider sag”.

STATIC SAG- This is how much the bikes weight acts upon the rear suspension. Measure the difference between the bike at rest and the rear shock fully extended by lifting the rear of the bike. The difference is 'Static Sag'
RIDER SAG- This is how much the riders weight acts upon the rear suspension. This is the amount the bike drops with all your body weight as you sit on the bike. Measure the difference between the compressed shock as the rider is sitting on it (Both feet on the pegs) and the shock at full extension (again... by lifting the rear of the bike).

A top racing suspension company suggest that rear wheel rider sag should be around 30-40mm and static sag should be around 5-10mm. This many vary depending on your bike and manufacturer. The more rider sag you have, the softer the bike suspension will be.

Therefore, if the rider sag is less than 30 mm then your preload is too hard, if it is more than 40 mm, then it is a bit soft. Once you have set your rider sag as close as possible between 30-40 mm, next, check your static sag. If you have more than 10mm then you may need stiffer springs. If however, if your static sag is less than 5mm or you have no static sag then your springs may be too hard for your weight.

If you have to compromise then try to have at least a bit of Static sag in order to stop the bike from topping out.

Many Books, videos, media and friends will all have different opinions on the figures quoted above (and below).
I will try to explain the underlying principles and effects of setting up your bike so that you, the rider, can make an educated decision on how you want your bike to perform.

Front Preload
Some people set the front suspension based on rider sag and static sag. This is especially useful in determining if you need softer or stiffer springs. If your bike is realitively new, you will already have the proper springs (unless you are preparing for MotoGP, but then you probably wouldn't be reading this article anyway :) Use the same system as above to determine Rider sag (35-48mm) and Static sag (25-30mm).  However, I prefer the below method to optimize my current original front forks.
You want your bike to use as much front suspension "travel" as possible without "bottoming out" (no more travel) even in extreme conditions. So lets establish how much suspension travel you are currently using.
Wrap cable ties around the smooth part (stanchion) of your front forks near the rubber seal (top) of the front forks. Ensure that it does not scratch the stanchion and it is not too tight as to damage the rubber seals! (just tight enough to stay in place)
With the cable ties in place, ride your bike as normal using as many riding conditions (corners, braking, accelerating, wheelies and stoppies) that you are likely to meet. Then increase or decrease your preload until the cable tie stops about 10 mm before “bottoming out”.
Reducing preload should give you more travel. If the forks bottom out, reset the cable ties and increase preload until the cable tie stops around 10mm above the limit. You should always leave about 10mm travel for emergencies like slamming into unknown potholes.

 

 

DAY 3 - FRONT DAMPING

Both rebound and compression damping are best adjusted after riding your bike and feeling how it handles to you. You cannot use your friends settings. There is so much debate and controversy regarding suspension set up because it is a personal experience and depends on how and where you ride your motorcycle. Suspension setup is unique to every rider and riding style!
Some people, media or websites will charge or tell you what they think is best. Amongst top racers, suspension setup is a closely guarded secret. You have to find your own settings that you are comfortable with and take notes as you experiment with different settings. We will teach you the basics for each kind of rider... again, you will need to figure out which feels best.

 



tyre profiles

Setting the right amount of damping depends on the type of bike, how you ride the bike, and shape and pressure of tires you use. Also it depends on your riding style and how much suspension travel you want at any particular moment. This article will try to explain what to look out for and how to tweak it.

Note that your suspension will handle differently under different conditions, high or low speed, Temperature and wet or dry conditions, therefore experiment with setting up your bike under the conditions you would like to use them in.

To start with, set your bike damping rebound and compression to your manufacturers or your preferred setting.
I do not know the exact terminology used in your manufacturers owners manual but note that

Soft damping

=

little damping

=

decreased damping, soft, mushy ride

Hard damping

=

excessive damping

=

increased damping, stiffer, rough ride

Nose Up

Nose down


Front Compression
You need front compression under braking and when riding over uneven humps. You want your front suspension to compress slowly and controlled when you break. As your bike “nose dives” under braking, it transfers more weight over the front wheel. This helps slow the bike quicker.
If the front suspension compresses too quickly (too soft) you risk the suspension bottoming out and then your bike will feel vague and since it nose dives too quickly the back wheel may loose contact with the road and slide around laterally.  On the other hand when compression damping is too high the suspension can't react quickly enough to compress over bumps and will skip and chatter. You will have an uncomfortable ride and your braking is compromised, especially in the wet, not a good combination!

Another important aspect of front compression is when you brake just before a turn. As you brake before the corner, the bike will naturally “nose dive”, this will shorten the wheel base and alter the geometry of the bike, making the bike turn quicker into the corner. It is important that your bike compresses predictably and safely in a corner/turn.
SOFT: If your compression is too soft, your bike will nose dive too quickly, then as you turn into the corner, the bike will collapse into it and you end up having to compensate. 
HARD: On the other hand if you have too much front compression damping, do not get enough nose dive and the bike will be reluctant to turn, and may drift wide on entry to the corner.

Go for a ride on your bike and try braking and turning into corners at different speeds. This will cause a bit of nose dive so try different settings. If your bike bottoms out, increase the front preload. (See preload notes above) Always remember to keep notes.



Front Rebound
Front rebound damping controls the rate at which the bike “sits up” after the front suspension has been compressed. If it is too soft, the front end will pop up too quickly after any situation causing the rear suspension to compress and causing the bike to "see-saw". This may result in lack of traction.  If rebound damping is too high you may have lack of “feedback” and in extreme cases where the suspension can't react quickly enough to extend again it will pump down until it bottoms out, which is very dangerous.

An alternative to manufacturers setting for front rebound is to place your bike on level ground and have your mate or rear wheel stand support the back of the bike. Press hard on the top of the yoke without pressing the brakes and let go. The suspension should rebound to its original position within a second.
If it takes more than a second then you need softer rebound but if it takes less than a second or it rebounds past its original position then you should make your rebound harder. This method may work but really it is too simplistic for real world riding.

One critical area where you want your front rebound to work well is through the corners and turns. As you fly down the road and brake before or into the corner, the front suspension compresses, then as you let go of the brakes, the front wheel will rebound fully. You do not want your front end to sit up too quickly especially mid corner, loss of front wheel traction in a corner is a death sentance.
SOFT: If it rebounds too quickly in the corner your bike will sit up very quickly creating a longer wheel base. The front wheel “shooting” out also causes the bike to drift wide or a feeling of the front end “washing out”. If this happens, increase (harden) your rebound to slow the rate the front wheel rebounds.
HARD: On the other hand if the rebound is too hard, when you let go of the brakes and on to the throttle in a corner, because the wheel is compressed for longer you will have a shorter wheel base for longer. This may cause the bike to feel wooden in the corner and turn too quickly.

To set up your front rebound damping you are going to have to go through a few corners a few times and it is best that you have sorted out the preload and front compression first. Basically you want to be able to brake hard either before the turn or up to the apex of the turn, (whichever type of riding suits you) then let go of the brakes and get on the throttle without the bike “see-sawing” (diving at the ground when braking, and the front sitting up under acceleration).


NOTES
Advanced damping control
Since most accidents happen in a turn, I will suggest that you set up your bike for cornering. Try to get the bike to enter and exit a corner with minimal rocking or see-sawing to the front end. These setting should be ok for bumpy tarmac as well.
Keep a record
Keep a note of the settings you are using as well as a journal of what you have used. What was different? How did/does it feel? What was the tire pressure? Different tires shapes, sizes and pressure can affect your readings and therefore you may want to keep a record of all your settings especially if you are a track addict or racer. A simple temperature change can effect performance. Keep a note of the weather. Cooler temperatures will thicken the oil in your forks and initially firm up your tires. While on a hotter day, your fork oil may thin a bit, while allowing your tires to become 'sticky' and increase traction. By keeping a journal you will get to your 'perfect' setting and you eliminate having to go through all this again! Trust me... KEEP A JOURNAL!!!
Counting Clicks
If your bike uses clicks to adjust compression and damping, and you want to adjust your damping settings, refrain from turning it a few clicks till you 'think' you have the 'correct' new settings. Fully count the clicks in each direction to ensure you were on the right 'old settings', then count it out again for the new settings. Example; you think your front compression is on 5 clicks out and you want to try 7 clicks out. Do not simply turn it 2 clicks out. Count the 5 click in, and then count the 7 clicks out!
Set Up
Do not adjust more than one setting at a time unless it is to a previously recorded set up as you will not know which setting caused the most effect. I commute to work and I used to make one small (a click) adjustment a day. Sometimes I would leave it for a week because the conditions where not right to feel the new settings in action. On the track, I would suggest one setting change per session, minimum. Take note of what changed!! Write it down!! Soon you will have the 'perfect combination'.
Altering Bike Geometry
You can alter your bikes geometry by sliding your front forks up through your front yoke (triple trees).. i.e. your forks will stick up through the yoke a bit more than standard thereby causing your bike to have a more nose down bias. This makes the bike turn in faster, it doesn't increase the corner speed and you will loose a slight bit of ground clearance (CBR riders take note)
 I do not recommend moving your front forks more than 5mm.

 

DAY 4 - REAR DAMPING


Kick Up

Squatting


Once you are done with the preload/sag and front wheel damping, let's move onto the rear wheel. You can set it based on comfort and uneven roads using the same methods as you would with the front wheel. Also you could try to do what’s called:

Suspension Balance
Take the bike off its stand onto level ground and stand next to it. While holding your motorcycle upright, put one foot on the foot peg next to you and press hard on it. The front and rear of the bike should squash down and return to original starting position in unison. If the bike doesn't, adjust rear damping compression and rebound to compensate.

Now you have a comfortable bike with adequate suspension balance. Now let’s fine tune it a bit. Again there are no tricks to setting up your rear wheel suspension. You will need to understand what causes your rear suspension to work. Since rebound occurs after compression we will deal with compression first.

Rear Compression
Like with the front wheel, if your rear compression is too hard you will have an uncomfortable ride because the rear wheel simply bounces off bumps and ripples in the road, giving you a disconnected 'feel'. Conversely, if it is too soft, you may get excessive “squatting” under heavy acceleration causing the bike to feel lethargic, unresponsive and even “bottoming out” on rough roads.
When you accelerate, you need a bit of rear end squatting to give the tires a chance to get some traction and absorb excessive power to the back wheel. However, it is that squatting action under heavy acceleration that can cause problems when coming out of corners, essentially disconnecting the front wheel from the pavement.

SOFT: Let’s imagine that you are exiting a corner on your motorcycle, and the bike is leaned over as you start to accelerate smartly. If the compression damping is too soft, you will get too much rear end “squatting” causing a “nose up” situation. This will cause your bike to drift wide on exit of the corner, loosing precious turning capability. This is not the same as a too much front compression damping which also causes the bike to drift wide on entry into the corner.
HARD: On the other hand if your rear compression damping is too hard, you will not get enough “squatting” and therefore may not get enough traction. This will cause a bit of rear wheel spin, or the rear wheel suddenly “kicking up”. You can imagine what would happen in extreme circumstances.

To set your rear compression damping up properly, it is best to have the front end sorted out first. That way you know you that your entry into the corner is as smooth as possible. Next, you want to roll on the gas as you exit the corner and your bike should hold it's line and inspire confidence!


Rear Rebound
You are nearly finished setting up your bike :) You have exited the corner and the bike is now flying forward in a straight line. At this point you want the rear rebound damping to keep the rear wheel in contact with the road, thereby giving you maximum traction
SOFT: However if it is a long corner then your rear rebound will come into play mid-corner. If your rear wheel kicks up too quickly, it will unsettle the chassis of the bike making it “wallow” and “lurch” mid corner. A lot of people wrongly try to cure mid comer “wallowing” by increasing rear preload. This may "stiffen" the rear end but you may loose a bit of suspension travel. The cure is to increase (harden) rear rebound.
HARD: However, if your rear suspension is too hard, your back wheel will not sit up quick enough. This will cause you the have the back end squatting causing a “nose up “ situation for longer. This may cause you to drift wide, similar to the effects of soft compression. Also, since the rear shock would not extend quick enough, you may get a feeling of vagueness or loss of traction, skipping the rear tire across the bumps in the pavement.

That’s it!!
Ultimately you decide how you want your suspension setup. You ride your bike and no one else... What feels good to you may not be the correct setup for another. Some push the bike hard into turns, leaning and draggin' a knee; most riders don't! The setup for each rider will be completely different... so once again, it is up to you to determine what feels and works best for your style of riding. There is no magic formula, and everybody has their opinion. Writin in this article is the simple facts that will head you in the right direction. So educate yourself, then go out and ride. Keep tweaking the bike until it feels right!!!

I can't stress enough how critical your suspension is!! With a poorly setup suspension, you will NEVER get better and riding will become a chore! Riding will become hard work... harder than it has ever been!!! A bike which setup to your body and riding style will become the most fun you've ever had on two wheels. You will ride faster and with more confidence, inspiring learnig and improving your skils everytime you ride!!

 

 

SUMMARY

So what did we learn?
- First, get your owner's manual out, familiarize and compare your current suspension settings with the recommended settings in the manufactures hand book. Still not satisfied?
- Then, set-up your preload, front and rear, so that you can use as much suspension travel as possible when riding your bike. This is based on your weight, so if your weight fluctuates then keep an eye on it.
- Next, adjust your damping so that your suspension does not compress or rebound too fast or too slow to upset the bike and be uncomfortable. What is too fast or two slow? if your bike has '15 clicks' for each adjustment, you won't want to be at 15, and you wouldn't want to be at 0. Somewhere in the middle (between 3 and 12, depending if you are a speed demon or a Sunday afternoon cruiser.


1 - Front compression
This is when you want your front compression to control the "nose down" effects of braking so it turns in to corner properly
2 - Front rebound
You have let go of brakes, adjust front rebound so that the front forks extend at a controlled rate allowing you to keep your line.
3 - Rear Compression
You want the rear end to squat a bit as you apply the power.
Make sure that the rear rebound setting keeps the rear wheel in contact with the road.

 Note: this image is only for illustration only. Your braking, turning and exit points and lines may vary, especially in the wet.

 

CONCLUSION
The point of this article is to educate you on how your suspension works so you can attempt to sort it out yourself. You should be able to feel the bike through the handle bars and the bike seat and be brave enough to note down the current settings and have a go at altering it to suit yourself.
I found that it is difficult to set up the bike for all condition. I recently changed my front brake pads and they were biting harder which made the bike nose down quicker. As summer approaches, I like to ride a bit faster. My weight is fluctuating. All these scenarios have caused me to change my setup. Top racers alter their setup at every track.
However if you are not competent with DIY, remember that if it isn't broke, don't fix it!

 

Special Thanks to Sean Onipede and www.gostar-racing.com/ For providing much of the information.

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