For a rider's safety, mirrors matter as much as tyres or brakes. A mirror that has worked loose and droops at speed, or a pivot that will not turn, leaves a blind spot exactly when you change lanes.
Check the adjustment before every ride: you should see only a small part of your shoulder, with the rest of the view showing the road behind. Even well set mirrors do not remove blind spots completely, so always look over your shoulder before a manoeuvre.
What you will need
Important: Keep the spray off the handlebar grips, brake levers and brake disc: your hands and brakes must grip reliably. Always wipe the mirror glass completely dry afterwards so no film distorts the image.
Step 1
Clean the glass and housing
Dust, insects and road spray reduce visibility. Soften dried insects with a damp cloth, then clean the glass with glass cleaner and a microfibre cloth without pressing hard, to avoid scratches.
Wash the mirror housing with warm water, especially after salted winter roads.
Step 2
Lubricate the mirror pivot
Fold the mirror all the way in. Use the precision straw of WD-40 Smart Straw to apply it right into the pivot. On metal mirrors this also protects against rust and corrosion.
Open and fold the mirror several times so it works inside, and check that it moves without effort but does not droop. Wipe off any excess with a clean dry cloth.
Step 3
Free a seized thread
The mirror stem is held in its handlebar bracket by a nut that seizes over time. If you cannot loosen it to adjust the mirror, apply WD-40 Specialist Penetrant to the thread and wait 10-15 minutes.
Loosen the nut, position the mirror and tighten it again without overdoing it.
Step 4
Protect the stems from rust
Metal stems and brackets suffer from moisture and salt in winter and rain. Spray a little WD-40 Smart Straw onto a cloth and wipe them with a thin film.
The film displaces moisture and stops rust forming on chrome or paint.
Step 5
Adjust the mirrors
Sit on the bike in your normal riding position and set each mirror so you see just the edge of your shoulder and as much of the road behind as possible.
After adjusting, check that the mirror does not shift with vibration at idle. If it does, tighten the fixing a little more.
Tip: If the bike goes under a cover for winter, treat the mirror pivots and stems with
WD-40 Smart Straw before laying it up: in spring they will be free of rust and will not seize.
What next
Check the adjustment before every ride and lubricate the pivots every few months and after washing. The same WD-40 Multi-Use is handy for cables, footrests and the ignition lock.
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».