By DSP Racing

Below is a reference guide to getting your linkage based late model off-road/Motocross bike
suspension spring rates. Please note that this is a recommendation to get you in the ball park.
Fine tuning and testing will be needed to get the best match for your application.

Check your bike's manual

to see what your stock spring rates are and what rider's weight range it is designated for. Some manuals will also have a   chart specifying what spring rates to use for different rider weights and applications.

• Note: if you have bought your bike 2nd hand and are not sure of what spring rates are currently on your bike, DSP Racing offers a free spring rate tests. Contact us for further information.

Setting your rear sag

is one of the most important suspension setup procedures. Again your manual will be a good starting point for where your race sag should be and static sag range.
Once your race sag is set, check your static sag to make sure it is in the allowed range.

• More race sag will make bike more stable (susceptible to under-steer)
• Less race sag will make bike turn better (susceptible to over-steer)
• Static sag is < less then specified range, need stiffer shock spring
• Static sag is > greater then specified range, need softer shock spring

General rule of thumb for getting spring rates for out of designed weight range

• For every 10 lbs over designed rider weight: add 0.1 kg/mm to shock spring rate and
  0.01 kg/mm to fork spring rates
• For every 10 lbs under designed rider weight: reduce 0.1 kg/mm to shock spring rate
  and 0.01 kg/mm to fork spring rates

Additional factors in choosing your correct rear shock spring rate

• Oversize Tank: stiffer
• Terrain:
  • Sand: stiffer
  • Mud: stiffer
  • Rock: softer
  • Rough: softer
  • Large jumps: stiffer
• Rear Axle Block Position:
  • Longer wheel base: stiffer
  • Shorter wheel base: softer
• Aggressive riding: stiffer
• Height: Taller riders can go stiffer in rear spring rate

Additional factors in choosing your correct fork spring rates

• Oversize Tank: stiffer
  • Terrain:
  • Sand: stiffer
  • Mud: stiff
  • Rock: softerer
  • Rough: softer
  • Large jumps: stiffer
• Rear Axle Block Position:
  • Longer wheel base: softer
  • Shorter wheel base: stiffer
• Aggressive riding: stiffer