Inflate them slowly. If the treads are just slightly worn, there's still life left. But if the rubber is so degraded that you can see threads or any sidewall damage, replace your tire.
#2 WheelsOpen quick-releases and, using a wrench, check that the axle nuts are securely fastened. Eyeball the wheels to make sure they're centered in the fork and frame.
If the brake pads look shiny, rough them up gently with sandpaper and wipe down the rims of your wheels with a clean rag. If the pads are worn (the grooves are nearly gone), replace them before your first ride.
More: Bike Care for Race Day
#4 PartsWipe down the components, frame, and wheels, and look for anything that needs attention. (If you think a thorough cleaning is necessary, follow these 7 Tips to Washing Your Bike.) Secure tattered tape or loose grips, and use a degreaser on gummed-up cables and housing. Don't ride if cables look frayed or rusted; replace them first.
Over time, lube dries up. After cleaning the grime from moving parts such as chain links and derailleur and brake-pivot points, apply fresh lube.
#6 InventoryCheck that your spare tube still holds air, the glue in your patch kit hasn't dried up, and your seat bag is stocked with get-home tools such as levers and a multi-tool.
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