A suspension fork and rear shock suffer most from dirt: dust, sand and water settle on the stanchions next to the seals, and every compression drags grime inside. This scratches the coating, damages the seals, and the fork starts to feel stiff, knock or leak.
Simple regular care after rides greatly extends the life of the suspension and keeps it sensitive over small bumps. The guide suits both leisure and mountain bikes.
What you will need
Important: Keep lubricants away from brake discs, pads and rims: contamination seriously reduces braking. Cover the brake with a rag before applying anything. Do not wash the bike with a high-pressure jet: water gets past the seals and into bearings.
Step 1
Wash the bike
After a muddy ride, wash the whole bike first. Go over the frame, fork and shock with a sponge, warm water and mild detergent, paying attention to the area around the seals. Rinse with a gentle stream or from a bucket and let it drain.
Step 2
Clean the stanchions
With a clean, damp microfibre, wipe the stanchions (the shiny tubes that slide into the seals) and the rear shock shaft. Wipe so you lift the sand away rather than pushing it under the seal. Do this after every ride, even a short one: it does more than anything to protect the seals from wear. Dry the stanchions.
Step 3
Lubricate the dust seals
Cover the brake disc with a rag. Apply WD-40 Specialist Silicone to the top of each stanchion where it enters the seal, and to the shock shaft next to its seal. Silicone reduces friction between rubber and metal, keeps the seals from drying out and repels water and dust.
Step 4
Cycle the suspension and wipe off excess
Push down on the bars and saddle several times, as if riding over bumps, to work the lubricant into the seal. Wipe off the excess and any dirt pushed out from under the seal with a clean rag. Only a barely visible film should remain on the stanchions, as excess lubricant attracts dust. A thin film of WD-40 Smart Straw on the metal mounting bolts and axle helps protect them from corrosion, but apply it precisely, well away from the brakes.
Step 5
Repeat regularly and watch the condition
If you ride a lot, lubricate every two weeks and clean the stanchions after every ride. If the stanchions are scratched, oil seeps from under the seals or the fork still moves unevenly after care, internal servicing cannot wait: take it to a bike workshop to have the seals and oil replaced to the fork maker's schedule.
Tip: Before winter storage, clean the fork, treat the seals with
WD-40 Specialist Silicone and keep the bike somewhere dry. In spring, repeat the treatment before your first ride.
What next
Clean, lubricated suspension works more smoothly and lasts longer. Do not forget the chain, cables and derailleurs alongside the fork: they need the same regular care.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
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