Pedals only get attention when they start creaking or seize in the crank so hard they will not budge. A seized pedal is especially bad news with aluminium cranks: forcing it can easily strip the thread, and then the crank has to be replaced.
To avoid this, remove the pedals once a season, clean the threads and grease them. It is also a good moment to check the pedal bearings.
What you will need
Important: The left pedal has a left hand thread. Seen from the saddle, the left pedal undoes clockwise and the right anticlockwise. Never force a pedal the wrong way, as that strips the crank thread.
Step 1
Choose the right tool
Pedals come off either with a flat 15 mm pedal spanner on the axle flats or with an 8 mm (sometimes 6 mm) hex key from the back of the crank. Check which your pedals use and make sure the tool fits fully with no play.
Step 2
Unscrew the pedals carefully
Before undoing them, spray WD-40 Smart Straw through the straw onto the joint between pedal axle and crank from both sides and leave it a few minutes to work into the thread. This reduces the risk of damaging the thread in an aluminium crank.
If the hex socket in the axle is packed with dirt, clean it out with the same product first so the key seats fully. Turn the right pedal anticlockwise and the left clockwise, smoothly and without jerking.
Step 3
Clean the threads and pedal bodies
Spray WD-40 Smart Straw on the pedal threads and the threads in the cranks, scrub with the brush and wipe dry. Clean mud and sand from the pedal bodies and from clipless mechanisms too: springs and cleat retention should work crisply.
Step 4
Check the pedal bearings
Spin the pedal axle with your fingers and rock the body. The pedal should turn smoothly with no grinding or noticeable play. If you feel play or roughness, the bearings need servicing or the pedals should be replaced.
Step 5
Grease and refit the pedals
Apply a thin layer of WD-40 Specialist White Lithium Grease to each pedal thread. Find the markings on the axles: L for left, R for right.
Start each pedal by hand so the thread does not cross, then tighten with the spanner. Greased threads will not seize and will undo easily next time.
Tip: If a pedal is still stuck, set the crank horizontal, fit the spanner on the axle and push down on it with your foot while holding the opposite crank, always in the correct undoing direction.
What next
Remove and grease the pedals once a season, and more often after winter rides on salted roads. To protect other metal parts of the bike from damp during storage, use WD-40 Multi-Use.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».