Why this happens
Suspension keeps the tyres in contact with the road and absorbs potholes that would otherwise shake the frame, battery and electronics. Fork seals and shock seals wear and let dirt in or oil out, which reduces damping. Bushings wear and develop play. Simple cleaning and inspection extends their life and shows when a service is needed.
What you need
Tools
- Torch
- Clean cloth
- Centre stand or paddock stand
- Steel rule (optional)
Materials
- Mild soapy water
- Suspension-safe silicone spray or seal lubricant (only if the manual allows)
Before you start
- Do not open fork legs or shocks at home; they contain oil and springs under pressure, and some shocks are gas-charged.
- Never ride if fork oil has reached the brake disc or pads.
- Keep all lubricants away from brakes and tyres.
Step by step
- 1
Power off and clean
Turn the key off and park on the centre stand. Wipe the fork legs and rear shock body with a damp cloth to remove dust and mud. Pay attention to the shiny fork tubes and the area just above the seals, where grit builds up and damages the seals.
- 2
Look for oil leaks
With a torch, look at the top of each fork slider, just below the seal, and along the rear shock body. An oily film or ring of grime around the seal shows that oil is leaking. Check that the brake caliper and disc are free of oil; if fork oil reaches the brake, the scooter is unsafe to ride.
- 3
Inspect for damage
Check the fork tubes for scratches, dents and rust spots, which damage seals with every stroke. Look for bent fork legs by comparing both sides, and check the rear shock for a bent shaft, cracked mounts or a broken spring. Look at the mounting bolts for tightness.
- 4
Do a compression test
Take the scooter off the stand. Hold the front brake and push down firmly on the handlebars several times. The fork should compress smoothly and return without bouncing more than once. Repeat for the rear by pressing on the seat. A knock, a stuck feeling or bouncing like a spring suggests worn damping or bushings.
- 5
Check for play
With the front wheel lifted on the stand, hold the bottom of the fork legs and try to move them forwards and backwards. Movement felt at the sliders points to worn fork bushings. Check the rear shock mounts by lifting the rear wheel slightly and feeling for clunks.
- 6
Adjust preload if available
If your rear shock has a preload adjuster, check the manual for the recommended setting for solo and pillion riding. Adjust it with the correct tool, setting both sides equally on twin shocks. Correct preload keeps the scooter level and prevents bottoming out on speed breakers.
- 7
Protect the seals
After cleaning, wipe the fork tubes dry. If the manual permits, apply a very light film of suspension-safe lubricant to the tubes and work the fork a few times, then wipe off the excess. Never let lubricant reach the brakes or tyres.
How to tell it worked
Fork tubes and shock are clean and dry, there are no leaks or bends, the suspension moves smoothly and returns without bouncing, and preload is set for your load.
Stop and call a technician if
- Oil is leaking from a fork seal or shock.
- A fork leg, shock shaft or mount is bent or cracked.
- The suspension knocks, sticks or bounces repeatedly.
- There is clear play at the fork bushings or shock mounts.
Questions
How often do scooter forks need servicing?
Follow the interval in your service manual. Inspect them monthly and service sooner if you see leaks or feel changes in damping.
Can bad suspension affect my EV's battery?
Worn suspension passes more shock and vibration to the frame and the components mounted on it. Keeping the suspension healthy helps protect connectors and mounts as well as your comfort.