Bike repairing is a technical job. So many people will go to the bicycle repair shop for the first time when their bike brakes down.
But the technician maybe just tighten the screws, the so-called problem is solved.
In order to avoid similar situations, 16 kinds of common faults of bicycles are sorted out to help people judge the condition of vehicles
Fault 1: There is a noise when pedaling.
Reasons and Suggestions:
When the connection of the crank, bottom, and pedal is loose, there will be a noise. Or the noise is produced by friction.
Take the crank bolt loosing as an example, tighten the crank bolt. If the crank still rings, remove it, coat a layer of grease on the bottom, and then reinstall the crank.
Fault 2: The transmission line rubs against the frame and a piece of paint is rubbed off.
How to solve this problem:
Stick anti-friction silica gel or rhinoceros skin anti-friction belt at the contact place.
Problem 3: The flywheel is rusty.
How To Solve:
Rust is not serious, more use of lubricating oil can prevent continued rusting. And the chain will wear off some rust during riding.
Fault 4: The rear derailleur keeps making a sharp noise.
Reasons And Solutions:
1. The coupler is deformed due to falling or rubbing. Check whether there is deviation. If the deviation is serious, it is recommended to replace it directly.
2. The guide wheel has not been cleaned for a long time, and there are a lot of stolen goods. First clean with a cleaning agent, then add lubricating oil for lubrication and wipe off the excess oil.
3. The outer corner of the guide wheel is seriously worn, and abnormal noise may also occur when the obtuse angle is ground into a sharp angle. In this case, it is recommended to replace the guide wheel.
Fault 5: Abnormal noise of chain.
Reasons: The chain is short of oil and the chain pieces are not lubricated sufficiently.
Solution: Add chain oil or lubricant and wipe off the excess oil.
Fault 6: When using a certain gear ratio, gear jumping occurs when pedaling.
Reasons And Solution:
If there are foreign objects such as mud, weeds, leaves, branches, and so on between the flywheels, dig them out.
Because it will hinder the normal engagement of the chain and flywheel. If not, the flywheel may have worn out and the chain and flywheel usually need to be replaced.
Fault 7: V brake is weak, but the brake block is not seriously worn.
Reasons: The brake line is loose or the CNC rim stripe is worn seriously.
How To Solve:
Turn the brake fine adjustment nut counterclockwise (generally near the brake caliper or brake hand, the end of the brake line pipe), so that the brake block is close to the rim. Adjust sensitivity according to personal habits.
Fault 8: Squeal when braking.
Reasons And Solutions:
1. Due to the quality of the brake pads or the hard brake pads used, abnormal noise is easy to occur. The brake pads with good quality or soft brake pads can be replaced.
2. Due to installation or external force, the brake skin has been tilted, and the bonding surface is uneven, even touching the outer tire. At this point, readjust the brake.
3. The aluminum chip attached to the brake pad rubs with the rim. The sandpaper or file can be used to grind the brake block to remove the aluminum chips on the surface.
Fault 9: It rotates when the screw is removed.
Reasons And Solution:
Fix it in the groove on the back of the disc nail with a slotted screwdriver or special screw tool, and then remove it.
Fault 10: The pedal falls off.
Reasons And Solutions:
After the pedal falls off, check whether the thread connecting the pedal on the crank is complete. If it is intact, install the pedal back and tighten the screw. (be sure to tighten the screw with tools, only by hand, not enough force). If the screw thread of the foot pedal is damaged, you can not continue riding, only replace the crank.
Fault 11: The crank falls off.
Reasons And Solution:
The crank falling off is caused by the screw loosening of the fixed crank, and the screw of the fixed crank will be slightly loosened during daily riding. Check regularly and fix with hexagon socket.
Fault 12: The tire is cracked.
Reasons:
The complex road conditions of long-distance and cross-country riding can easily lead to the tire rupture. If the tire is not repaired in time, the inner tube may burst.
How To Solve:
First, check whether the crack is on the front or side of the tire. If it is on the side, the outer tire needs to be replaced immediately; if it is on the front, the crack does not exceed 0.5cm, and a special patch can be used to repair the tear temporarily (for example, park tool has such products).
Fault 13: Tire pins.
How To Solve:
The nail should be taken out as soon as possible after the tire is punctured, so as to prevent the inner tube from being punctured many times. If the number of holes in the inner tube is small, you can repair it with your own tire repair tool, or replace the inner tube directly.
Fault 14: After mending the inner tube, it is flat again just after being installed.
Reasons:
The cushioned belt is misplaced or foreign body remains in the tire.
How To Solve:
If the hole in the inner tube is on the inner side, the cushioned belt may be misplaced, resulting in the inner tube being cut by the spokes; if it is on the outside, there may be some small and sharp foreign bodies in the outer tube. Use your fingers to carefully feel the inside of the tire to find the foreign body and remove it.
Fault 15: Often puncture.
Reasons:
The tire pressure is too low, or the riding speed is too fast, and the road condition is not paid attention to in time.
How To Solve:
There is a standard pressure value on the tire. For ordinary riders, it is recommended that the maximum tire pressure should be 140 psi to the lowest 120 psi. This pressure value comes from the test. If the tire pressure exceeds 140 psi, it will increase the rolling resistance. If it is too low, it will be easy to tire. In addition, slow detour is recommended when the road condition is poor.
Fault 16: The patch does not adhere to the inner tube.
Reasons:
The inner tube is not roughened enough, and there are still many impurities on the surface; there is an air gap between the patch and the tire; there is less glue, and the patch is moved when it is not completely dry.
How To Solve:
Roughen the inner tube, mark the crack when it is found, apply more glue, and make sure that the crack is at the center of the patch when sticking. Give glue enough time to dry, about 5 minutes. Of course, you can also choose a simple, fast tire patch.