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A few articles I wrote for my CBRTech web site a long time ago, in a galaxy far far away 
Bike Sag
There are two types, Static and Loaded.
Static sag is the amount the bike suspension settles under its own weight.
Loaded sag is the amount the bike suspension settles with a rider on board.
Road bikes have a wide range of bumps and potholes to negotiate so the suspension needs to be set slightly soft. Race bikes on the other hand are set up harder than road bikes because the race tracks they ride on are generally smoother and void of potholes.
The correct settings are: (this was for the CBR1000RR)
Static Street Race
Front 20-25mm 10-20mm
Rear 15-20mm 10-20mm
Loaded Street Race
Front 35-50mm 25-35mm
Rear 30-40mm 20-25mm
Most of you will find that you will need to change springs to get into the right range.
Without the sag set correctly the damping will never be able to work effectively, because the suspension will be trying to overcome the effects of an incorrect spring.
So how do we set the sag and determine if we have the correct springs?
First off you will need the following.
A tape measure. (that reads in mm)
A pen and paper.
Tools to adjust the front and rear preload. (in your Honda tool bag)
Two strong friends.
Static Sag
Lift the back wheel of the bike off the floor with a floor jack.
With the bike on the side stand, place the jack under the oil pan (put a piece of wood between the jack and the oil pan) and raise the wheel just a hair off the ground.
Now, using your tape measure, take a reading from the centre of the rear wheel spindle to a point on the tailpiece that is directly above the spindle. Write down the rear no load measurement and assign it as reading A.
Next, raise the rear wheel about 2 inches off the ground and get your friend to push down on the passenger seat - this should unload the front forks.
Measure from the bottom yoke to the top of the stanchion. Write down the front no load measurement and assign it as reading C.
Measurements A & C will remain the same throughout the procedure so you only need to take this reading once.
Now put the bike back down on its wheels and hold it upright. The bike will settle under Its own weight. Measure the distance from the spindle to the tailpiece. Write down the rear Static measurement and assign it as reading B.
Subtract B from A. This is your rear static sag. Keep a note of it just in case you want to change it back. Ideally you are looking for 15-20mm on a road bike and 5-10mm on a race bike.
Either compress or loosen off the spring to get into this range using the tool supplied in your tool kit
Perform the same operation for the front, Measure from the bottom yoke to the top of the stanchion. Write down the front Static measurement and assign it as reading D.
Subtract D from C. This is your front static sag reading. Keep a note of it just in case you want to change it back. Ideally you are looking for 20-25mm on a road bike and 10-20mm on a race bike. Either compress or loosen the fork springs with the supplied honda tool to get in this range.
Loaded Sag
Sit on the bike with your riding gear on and have one friend steady the front and the other ready to measure. Sit the bike upright. Now WITHOUT touching the front or rear brakes bounce up and down a few times on the seat and then assume your normal riding position. Measure the rear of the bike as before. Write down the rear loaded measurement and assign it as reading E.
Subtract E from A and this gives you your rear loaded sag. Try and get between 30-40mm on a road bike and 20-25mm on a race bike by adjusting the spring preload as before.
Now do the same for the front. Write down the front loaded measurement and assign it as reading F. Subtract F from C and try to obtain 35-50mm on a road bike and 25-35m on a race bike.
If you can't get in these ranges for both Static and Loaded sag then you will need to change the springs for a harder or softer ones.
Bike Sag
There are two types, Static and Loaded.
Static sag is the amount the bike suspension settles under its own weight.
Loaded sag is the amount the bike suspension settles with a rider on board.
Road bikes have a wide range of bumps and potholes to negotiate so the suspension needs to be set slightly soft. Race bikes on the other hand are set up harder than road bikes because the race tracks they ride on are generally smoother and void of potholes.
The correct settings are: (this was for the CBR1000RR)
Static Street Race
Front 20-25mm 10-20mm
Rear 15-20mm 10-20mm
Loaded Street Race
Front 35-50mm 25-35mm
Rear 30-40mm 20-25mm
Most of you will find that you will need to change springs to get into the right range.
Without the sag set correctly the damping will never be able to work effectively, because the suspension will be trying to overcome the effects of an incorrect spring.
So how do we set the sag and determine if we have the correct springs?
First off you will need the following.
A tape measure. (that reads in mm)
A pen and paper.
Tools to adjust the front and rear preload. (in your Honda tool bag)
Two strong friends.
Static Sag
Lift the back wheel of the bike off the floor with a floor jack.
With the bike on the side stand, place the jack under the oil pan (put a piece of wood between the jack and the oil pan) and raise the wheel just a hair off the ground.
Now, using your tape measure, take a reading from the centre of the rear wheel spindle to a point on the tailpiece that is directly above the spindle. Write down the rear no load measurement and assign it as reading A.
Next, raise the rear wheel about 2 inches off the ground and get your friend to push down on the passenger seat - this should unload the front forks.
Measure from the bottom yoke to the top of the stanchion. Write down the front no load measurement and assign it as reading C.
Measurements A & C will remain the same throughout the procedure so you only need to take this reading once.
Now put the bike back down on its wheels and hold it upright. The bike will settle under Its own weight. Measure the distance from the spindle to the tailpiece. Write down the rear Static measurement and assign it as reading B.
Subtract B from A. This is your rear static sag. Keep a note of it just in case you want to change it back. Ideally you are looking for 15-20mm on a road bike and 5-10mm on a race bike.
Either compress or loosen off the spring to get into this range using the tool supplied in your tool kit
Perform the same operation for the front, Measure from the bottom yoke to the top of the stanchion. Write down the front Static measurement and assign it as reading D.
Subtract D from C. This is your front static sag reading. Keep a note of it just in case you want to change it back. Ideally you are looking for 20-25mm on a road bike and 10-20mm on a race bike. Either compress or loosen the fork springs with the supplied honda tool to get in this range.
Loaded Sag
Sit on the bike with your riding gear on and have one friend steady the front and the other ready to measure. Sit the bike upright. Now WITHOUT touching the front or rear brakes bounce up and down a few times on the seat and then assume your normal riding position. Measure the rear of the bike as before. Write down the rear loaded measurement and assign it as reading E.
Subtract E from A and this gives you your rear loaded sag. Try and get between 30-40mm on a road bike and 20-25mm on a race bike by adjusting the spring preload as before.
Now do the same for the front. Write down the front loaded measurement and assign it as reading F. Subtract F from C and try to obtain 35-50mm on a road bike and 25-35m on a race bike.
If you can't get in these ranges for both Static and Loaded sag then you will need to change the springs for a harder or softer ones.