Checking over your bike before leaving for a ride is an excellent preventative step but occasionally mechanical problems must be dealt with during a ride. In the event that a mechanical problem disrupts your ride, the following selection of topics may prove useful.
Carrying a few tools in a bag of some sort is a necessary precaution. There are a several basic items worth carrying along regardless of distance or conditions. Certainly a spare tube and maybe a patch kit are advisable. Depending on the duration of the ride, considerations must be made for additional necessities. A multitool spare tube, tire levers, pump and any other incidentals specific to your bike are generally worth packing along. Perhaps a couple tire boots and zip ties for good measure may be included. All of these items fit well into a bag situated beneath your saddle.
In the event of a flat, stop as soon as possible and find a suitable spot to stop. Remove the affected wheel from the frame. If your wheels are attached to the frame by way of a quick release, no tools are needed. On some bikes, the wheels are secured with a nut on each side of the axle and require a wrench to remove them. The brake may need to be opened in order to allow the wheel to pass through. Again, packing the appropriate tools for your bike is essential.
Once the wheel is free of the bicycle, use a set of tire levers to remove one side of the tire’s bead from the rim. The stiff, reinforced edge of the tire that engages with the rim is called the bead. Pay particular attention to the arrangement of the tire and tube relative to one another. Once the tube has been removed, over-inflate it to approximately twice its size. To locate the puncture, run it past your cheek. Remember to examine the inside surface of the tube closest to the rim. Check for material still lodged in the tire. A small piece of wire or glass may not be visible from the outside of the tire. Examine the inside by turning the tire inside out to expose any sharp bits. When the tire has been cleared of residual material, install a new tube, avoiding the use of tire levers when reinstalling the tire, as they are likely to pinch the new tube.
If you are using tubeless tires, packing along a tube is usually recommended. In the event that the tire burps or you encounter a large puncture, you will be glad to have that tube. The tire boot mentioned earlier is a stiff adhesive patch intended to stabilize your tire if a sizable gash is sustained. The boot can be cut to size and placed on the inside of the tire, sandwiched between the tube and tire. It prevents the tube from escaping through the tire and bursting.
The possibility of breaking a spoke is greatly reduced by proper wheel maintenance. However, catching a bit of debris such as a stick or woodchuck in your spokes might be unavoidable at times. Tire pressure, angle of impact and the degree of preparation made by the rider all influence the possible outcome of an encounter with rough road conditions. Although long term concerns about wheel durability, assess the immediate damage and proceed accordingly. If the rim is too thoroughly bent, riding home is not an option. If a spoke breaks, the wheel will go out of true. On bikes with rim brakes, the rim likely will now rub on the pads. The broken spoke will move around and hit the frame or catch in the drive train. On a front wheel, the spoke can usually be removed. However on the rear, especially on the drive side where the gears obstruct removal, the spoke will have to be taped or wrapped around a neighboring one.
Loose Crank Arms
The cranks should have been properly affixed to the bike when it was built or last serviced. In the event that an arm comes loose, it is dangerous because at any moment it will abruptly fall off. Riding a loose crank arm also damages the arm and its accompanying parts. Tighten up the crank bolts with your multitool. On a splined crank arm, be sure that the splines of the crank arm are still aligned with those of the bottom bracket axle. The correct torque for these bolts can often be beyond the capacity of a multitool. It will be sufficient to ride home on usually but once you are back, use a proper wrench, preferably a torque wrench, on that bolt to ensure proper torque.
Having practiced a couple techniques such as the installation of a tube and a few other common mechanical methods will eventually come in handy. If a rehearsal can occur in the garage before a test is presented on the trail, all the better.