Motorcycle SAG calculator

Here you can find our Motorcycle SAG calculator so to adjust your suspensions spring preload according to your weight and the use of your bike.

You can download this calculator FREE using the link below.

By using it, you can adjust, according to your weight, your bike and the use you give to it (racetrack, road, off-road), the SAG in a very efficient way.

Also, it will tell you if your seals are worn and need a replacement, if your linkage system needs lubrication or if your spring rates are the correct ones.

Data to fill in:

Wheel travel: The total travel of the wheels (not the suspensions themselves). This data can be easily found on the Owner’s Manual.

Desired SAG %: Depending on the use you give to your bike, you will need a certain SAG value. In the instructions tab of the calculator you will find a recommendation chart.

L1: Length between two points (eg. between fork bottom bracket and dust seal on an upside down fork) with the wheel unloaded (in the air) not using paddock stands or similar that may compress the suspensions.

L2: Length between the exact same two points with the rider, with gear, on the bike, pushing the bike and letting it go to its relaxed position.

L3: Length between the exact same two points with the rider, with gear, on the bike, pulling the bike and letting it go to its relaxed position.

L4: Length between the exact same two points without the rider. This only should be taken once the correct SAG has been achieved.

Data given by the SAG calculator:

Recommended SAG: SAG lenght value based on the SAG% entered. (value to reach)

Actual SAG: Based on the entered lenghts, returns the actual SAG lenght.

Friction: friction lenght existitng on the suspension system. Turns Yellow if friction value is too big (need to check oil seals, dust seals, tie rods, etc.) If value is over the recommended, SAG can’t be adjusted properly.

Free SAG: Shows the motorcycle sag under its own weight, once rider SAG has been correctly adjusted. If cell turns blue it’s recommended to use a softer spring rate and set rider SAG again; if turns orange it’s recommended to use a harder spring rate and set rider SAG again.

How to use the Motorcycle SAG calculator

Introduce the following data: Wheel travel, % of desired SAG, measures L1, L2 and L3.

Adjust spring preload depending on the Actual SAG cell value. It must be the same or similar to the recommended SAG cell value.

Once correctly set, measure and type L4.

Adjust spring preload depending on the Actual SAG cell value. It must be the same or similar to the recommended SAG cell value.

Remember that this procedure will take you to the best baseline. You will be, probably, at one adjuster turn of the best set-up.

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