Fix a Puncture
The single most important cycling skill. Get stranded with a flat and no repair kit, and you're walking home. Practice at home before you need to do it roadside in the rain.
Global Cycling Network. Clear, professional, with roadside and workshop methods.
Carry a spare inner tube AND a patch kit. Swap the tube roadside (fast), patch the punctured one at home (saves money).
Run your fingers gently around the inside of the tyre before refitting — a thorn or glass shard left in the tyre will puncture the new tube immediately.
Check the valve type before buying tubes: Presta (thin, road bikes) or Schrader (car-type, hybrids/MTB). The SE Lager uses Presta.
Tyre levers: use proper ones, not screwdrivers. Screwdrivers pinch the new tube and cause another puncture.
Remove the wheel — release the brake, open quick-release or undo axle nuts
Deflate fully. Insert tyre lever under the bead, hook to a spoke
Use a second lever a few inches along to lift more bead over the rim
Slide the lever around to unseat one side of the tyre completely
Pull the inner tube out. Inflate it to find the puncture (listen/feel for air)
PATCH: Roughen around the hole with sandpaper. Apply rubber cement, let dry tacky. Press patch on firmly
OR swap for a new tube. Partially inflate the new tube before inserting
Tuck the tube into the tyre, ensuring it's not pinched anywhere
Lever the tyre bead back onto the rim. Start opposite the valve
Inflate to correct pressure (check tyre sidewall). Refit wheel, re-engage brake
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