The only aid to catching mechanical problems before they strand you is to develop a systematic pre-ride checklist. Several areas of any bicycle are worth checking regularly to help ensure a pleasant ride.
Bounce the bike tires on the floor and listen for rattling. A rattle might come from a loose headset or it could be loose bolts on a bottle cage. Pedals can also emit similar noises if they are worn or out of adjustment.
Wheels and Tires
A few aspects of tire health are worth checking before departing. Use a pressure gauge or short of that, a well calibrated squeeze to determine whether they need to be topped off. The recommended inflation for your tire can be found on the side of most tires and is indicated in PSI. Depending on several variables, the pressure you maintain will vary but knowing a minimum setting is beneficial. All tires are subject to wear and vulnerable to road detritus but maintaining sufficient pressure protects any tire from excessive wear and your wheel from added stress. Remember to check the degree of wear present on the tires. If they are squared off and rather thin on the center, it is probably time to replace them. Check all exterior surfaces of the tire, including the sidewalls. Also grab each wheel and push it side to side to check for hub bearing play.
Next, check the quick releases. Make sure that wheels are centered in the frame and fastened firmly. This step will aid the accuracy of assessing the condition and adjustment of your brakes. A wheel that is clamped off center in the frame will cause the brake pads to land unevenly and possibly contact the tire.
Now that the wheels are aligned in the frame, take a moment to examine the condition of your brakes. Start by spinning each wheel to check for rubbing. The pads should remain roughly equidistant from the rim as they are applied and contact the rim at the same time. Make sure that they are reasonably well aligned with the rim and do not contact the tire. Check brake pads for excessive wear and sufficient power. If the wheel wavers back and forth laterally enough to hit a brake pad when the brake is not being pulled, the wheel needs to be trued. Make certain that the pads are hitting the rim squarely below the tire so that they do not contact the tire and eventually abrade it to the point of rupturing.
Adequate chain lubrication prolongs the life of any chain. If the bicycle is ridden in damp, salty or otherwise inclement conditions for extended periods, the chain will need more regular lubrication than if it is only ridden mostly dry weather. It is possible to over sauce your chain however. The resulting soup of lubricant grab and retain grit that will speed the demise of drive-train parts. Always wipe down the chain after applying lubricant.
If you have access to a repair stand, checking over your bike is so much easier, especially assessing shifting performance. If a stand is not available, just take the bike for a quick spin to check the shifting quality. Make sure the gears shift smoothly and that the chain doesn’t skip or jump off the gears.
Take an inventory of your emergency kit. Do you have a pump, spare tube, tire levers, and multitool? Maybe a sandwich and vest? It is time to ride!