Common faults and solutions for bicycles

Repairing bicycles is a technical task. So in the eyes of many people, even if it is troublesome, the first choice after any breakdown of the bicycle is still to go to the repair shop. It turns out that the so-called fault may be a small problem that the repairer can solve by dripping the oil and tightening the screws. In order to avoid similar situations, today we have sorted out 16 common faults of bicycles to help you judge the condition of the bike:

1. There is noise when pedaling
Reasons and suggestions:
The three joints of the crank, axle core, and pedals are loose, or there is a sound caused by friction. Take the loose crank bolt as an example. The crank bolt can be tightened. If the crank still sounds, remove it, apply a layer of grease on the shaft core, and then reinstall the crank.

2. The cable line tube rubs against the frame and rubs off a piece of paint
How to solve:
You can stick anti-friction silicone or rhino leather anti-friction belt on the contact area, which is sold on major online sales platforms.

3. The bike cassette is rusty
How to solve:
If the rust is not serious, use more lubricating oil to prevent continued rust. At the same time, a part of the rust will be removed from the chain during cycling.

4. The rear derailleur continues to make a sharp noise
Reasons and solutions:
A. The tail hook has been deformed due to a crash or collision. Check for deviation, if the deviation is serious, it is recommended to replace it directly;
B. The guide wheel has not been cleaned for a long time, and there are a lot of stolen goods. First clean with detergent, then drip lubricating oil for lubrication, wipe off excess oil.
C. The outer corner of the guide wheel is severely worn. If the obtuse angle is ground into a sharp angle, abnormal noise may also occur. In this case, it is recommended to replace the guide wheel.

5. Abnormal noise in the chain
The reason:
It is caused by a lack of oil in the chain and insufficient lubrication between the chain pieces.

Solution:
Add chain oil or lubricant, and then wipe off excess oil.

6.  when using a certain gear ratio, the pedaling appears to jump teeth
Reasons and solutions:
If there are foreign objects such as mud, weeds, leaves, branches, etc. between the cassette, dig them out. Because it will hinder the normal engagement of the chain and the flywheel. If not, the sprocket may have worn out, and the chain and the sprocket usually need to be replaced.

7. The V brake is weak when braking, but the brake shoes pad are not worn seriously
The reason:
Due to loose brake cables or serious wear and tear on the CNC rims used on the body.

How to solve:
Turn the brake fine-tuning nut counterclockwise (usually near the brake caliper or brake hand, at the end of the brake line pipe) to bring the brake shoe close to the rim. Adjust the sensitivity level according to personal habits.

8. The brake pads make a sharp sound when braking
Reasons and solutions:
A. The quality of the brake pads or the hard brake pads used are prone to abnormal noise, and better quality brake pads or soft brake pads can be replaced.
B. The brake pad has been tilted due to installation or external force, and the fitting surface is uneven or even touching the tire. At this time, readjust the brakes.
C. The aluminum scraps attached to the brake pads rub against the rim. You can polish the brake pads with sandpaper or a file to remove the aluminum scraps on the surface.

9. it rotates when the nails are removed
Reasons and solutions:
Use a flat-head screwdriver or a special nail tool to fix it in the groove on the back of the nail, and then remove it.

10. Pedal fall off
Reasons and solutions:
After the pedal falls off, you should check whether the thread connecting the pedal on the crank is intact. If it is intact, install the pedal again and tighten the screw; (be sure to use a tool to tighten the screw, just use your hands, the strength is not enough) if installed If the thread of the pedal has been damaged, you cannot continue cycling and can only replace the crank.

11. The crank falls off
Reasons and solutions:
The crank falling off is caused by the screw that fixes the crank loss. Daily cycling will slightly loosen the screw that fixes the crank. Check regularly and fix it with an inner hexagon.

12. The tire is pierced by a nail

How to solve:
After the tire is pierced by the nail, the nail should be taken out as soon as possible to prevent the inner tube from being punctured multiple times. If the inner tube has a small number of holes, you can use your own tire repair tool to repair it, or you can directly replace the inner tube.

13. After the inner tube was patched up, it was deflated just after putting it back in

the reason:
Misalignment of the pad or foreign matter remaining in the outer tire.

How to solve:
If the hole in the inner tube is on the inner side, the strap may be misaligned, causing the inner tube to be cut by the spokes; if it is on the outer side, there may be some small and sharp foreign objects in the outer tube. Use your fingers to carefully explore the inside of the tire to find the foreign object and take it out.

14. Tires are often punctured
reason:
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:
The tire has a standard pressure value. For ordinary riders, the recommended tire pressure is from 140 psi to 120 psi. This pressure value comes from the test. When it exceeds 140 psi, it will increase the rolling resistance. If it is too low, it will be easy to puncture the tire. ; In addition, when the road conditions are poor, it is recommended to detour slowly.

15. The tire patch cannot be bonded to the inner tube
The reason:
The inner tube is not roughened enough, and there are more impurities on the surface; there is an air gap between the tire patch and the tire; there is less glue, and the tire patch is moved when it is not completely dry.

How to solve:
Clean the inner tube, mark the crack when you find it, apply more glue and make sure that the crack is in the center of the tire patch when sticking, and give the glue plenty of time to dry about 5 minutes. Of course, you can also choose a simple and fast rubber-free tire patch.

16: Tire burst
Reason: The complex road conditions of long-distance and off-road riding may easily cause the tire to split. If it is not repaired in time, it may cause the tire to blow out.

How to solve: First observe whether the crack is on the front or side of the tire. If it is on the side, you need to replace the tire immediately; if it is on the front and the crack does not exceed 0.5cm, you can temporarily repair the crack with a special patch (such as PARK TOOL) There are such products).