A dry squeak on every pedal stroke gets annoying within minutes, but more importantly it means the chain is running dry or clogged with dirt. Metal grinds on metal, and the chain, cassette and chainrings wear out many times faster.
A chain usually starts squeaking after rain, a wash or a winter ride on salted roads, when water has flushed out the old lube. It takes about 15 minutes to fix.
What you will need
Important: Keep all products off brake discs, pads and the rim braking surface. Cover the disc with a cloth while applying and wipe off any overspray at once.
Step 1
Make sure it really is the chain
Put the bike on a stand and turn the pedals by hand. A chain squeak is audible even without load. A squeak that appears only when riding under load often comes from the bottom bracket, pedals or saddle, and lubing the chain will not help.
Step 2
Clean the chain
Apply WD-40 Multi-Use along the whole chain while slowly backpedalling. Give it a few minutes to dissolve caked dirt and old lube and drive water out of the pins.
Hold a cloth round the chain and backpedal 10-15 times, and scrub the jockey wheels and sprockets with the toothbrush. Repeat until the cloth comes away almost clean.
Step 3
Find stiff links
Turn the chain slowly and watch it pass through the jockey wheels: a stiff link jumps as it goes through. Put a drop of WD-40 Multi-Use on it and flex the link with your fingers until it moves freely.
Check chain wear with a ruler or chain checker as well: a stretched chain should be replaced, as it wears out the cassette.
Step 4
Lubricate the chain
Let the chain dry for a few minutes. Apply WD-40 Bike chain lube to the inside of each link while backpedalling, then turn the cranks another 10-20 times to work it into the pins.
After 5-10 minutes, wipe the outside of the chain: lube is needed inside, and on the outside it only collects dust.
Step 5
Silence nearby squeaks
If the pedals creak in the cranks, remove them, clean the threads and apply a little WD-40 Smart Straw before refitting. Remember the left pedal unscrews clockwise.
Use the straw to treat the front and rear derailleur pivots too.
Tip: In dry summer weather choose a dry chain lube that picks up less dust; in autumn and winter use a heavier lube that resists rain and spray. The golden rule for any lube: apply it only to a clean, dry chain.
What next
Clean and lube the chain every 200-300 km and after every wet or muddy ride. After winter or a pressure wash, do not wait for the squeak: go over the chain with WD-40 Multi-Use and apply fresh chain lube straight away.
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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