Why is the cylinder head screw of a underbone motorcycle leaking engine oil?

What is the date for tire code 4621?

Tire code 4621 represents the production date of the tire, where 46 stands for the 46th week of the year, and 21 indicates the year 2021. Regarding tire parameters, they can be identified from the markings on the sidewall of the tire. Currently, almost all passenger car tires use radial tires. According to the identification method of radial passenger car tire specifications, the parameters are labeled in the order of "tire width, aspect ratio, compatible rim diameter, load index, and speed rating." If a tire's specification is 185/60R15-84H, its parameters are as follows: 185 indicates the tire width is 185mm; 60 represents the aspect ratio, meaning the section height is 60% of the width; R indicates that the tire is a radial tire, with the inner layer manufactured using the radial method; 15 is the rim diameter in inches; 84 is the load index, indicating a maximum load capacity of 500 kg, with four tires totaling 500×4=2000 kg; H refers to the speed rating of 210 km/h. Under normal circumstances, the shelf life of a tire is about 4-5 years. Even if the tire has been driven less, it still needs to be replaced once it exceeds its shelf life. When purchasing, pay attention to the production date and try not to buy tires that have been stored for more than 3 years. Since tires are rubber products, they will age over time, and their performance will deteriorate. If cracks appear, there is a higher risk of tire blowouts, which can affect driving safety.

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Can Out-of-Town Used Cars Be Licensed Locally?

Out-of-town used cars can be licensed locally. If you want to license a car purchased from another city locally, you only need to meet one condition: having the purchase invoice and vehicle certification, and then you can license it locally. When buying a car from another city and licensing it locally, there are several points to note: Purchase compulsory traffic insurance: There are two reasons for purchasing compulsory traffic insurance: first, the insurance policy is required for licensing; second, any vehicle on the road must have compulsory traffic insurance. Obtain temporary license plates: Without license plates or temporary license plates, motor vehicles are not allowed to operate. This is also a national legal requirement. There are two types of temporary license plates: one is only valid for driving within the city, and the other is valid nationwide. Be sure to obtain the nationwide temporary license plates.

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Will the car alarm when the engine oil is low?

When the car is low on engine oil, the oil warning light on the dashboard will illuminate to alert the owner that the oil needs to be replaced promptly. The oil warning light is symbolized by an oil can dripping oil, typically in red or yellow, and it indicates both the oil level and pressure inside the engine. Precautions for using engine oil: When checking the oil dipstick, pay attention to whether the oil level is between the maximum and minimum limits. If the oil level is too high, it should be reduced promptly; otherwise, it can increase the pressure in the crankcase, accelerating the aging and deformation of oil seals, ultimately leading to oil leaks and affecting the engine's lifespan. If the oil level is too low, stop and add oil immediately or wait for assistance, as it can accelerate the wear of pistons and cylinder walls. When the oil is severely lacking, the engine will quickly experience cylinder scuffing and piston seizure due to insufficient lubrication, leading to severe engine damage. When selecting engine oil, consider the following precautions: Choose engine oil based on the engine's requirements. It is unnecessary to use overly advanced oil in engines with lower requirements, nor should lower-grade oil be used in engines with higher requirements. Multi-grade oil is recommended as it is economical, long-lasting, and efficient, providing better protection for the engine. Due to the characteristics of multi-grade oil, it may appear darker prematurely and have lower oil pressure compared to conventional oil, which is normal.

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What is Neutral Gear on a Motorcycle?

Motorcycle neutral gear refers to a state where the motorcycle's engine is running but the motorcycle is not moving. Motorcycle gear classifications: Motorcycle gears are divided into sequential shifting and international shifting. Sequential shifting follows the order 123450, where after 5th gear comes 0 (neutral). International shifting: 102345, with neutral located between 1st and 2nd gear, acting as a half-step. The reason neutral is placed between 2nd gear: It facilitates easy access to low gears when needed; most of the time you can start in 1st gear or 2nd gear. After coasting in neutral, if you stop you can shift down to 1st gear to start, and if you don't stop, you can quickly shift up to 2nd gear or higher.

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What are the differences between 18-inch and 19-inch wheels?

18-inch and 19-inch wheels have similar tire widths, and the rolling radius error is less than 0.4%, which means they should have almost the same footprint. The differences are reflected in the following aspects: 1. From the perspective of braking performance: There is almost no difference in dry braking performance between 18-inch and 19-inch tires, while 19-inch tires perform faster in dry handling. However, 18-inch tires perform best in wet braking performance, and they also excel in cornering hydroplaning. Based on current objective data, there is almost no substantial difference between these two tire specifications. 2. From the perspective of subjective handling: During dry handling tests, the subjective feel of the tires shortens as the size increases. The fastest lap times with 19-inch tires are not because the larger wheel size provides more grip, but because these tires offer sharper and more responsive steering, while 18-inch tires make the car feel softer and less precise. 19-inch tires give the driver confidence and stability. The results of subjective wet handling tests are completely opposite. The confidence and predictability generated by larger tires in dry conditions are replaced by tension and faster loss of grip in wet conditions. Handling with 18-inch wheels is more concentrated at the front, meaning more caution is needed at the rear, whereas switching to 19-inch tires makes the entire car behave indecisively. 3. From the perspective of comfort and noise: 18-inch tires transmit more road bumps to the driver, especially at the rear of the car. The noise level of 18-inch tires is acceptable but noticeable inside the cabin. With 19-inch tires, the car feels entirely different, becoming harsh and offering poor comfort.

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Can Cars Operate Without Chips?

Only purely mechanical vehicles produced in the early stages do not require chips, whereas modern cars need them. Here are the specific details: Chip Shortage: This has become a global industrial issue, with some even referring to it as the "21st-century electronic oil crisis." This is not an exaggeration. As intelligence levels continue to rise, chips have permeated every aspect of daily life, and a shortage of chips can severely impact production and daily activities. The automotive manufacturing industry, as a pillar of the global economy, has been particularly affected. Repeated pandemic outbreaks and chip shortages have led international giants like Volkswagen, Toyota, Ford, and General Motors to announce multiple production cuts or temporary shutdowns to alleviate the issue. Domestic brands have also been impacted, with popular models from BYD, Geely, Great Wall, and Changan experiencing indefinitely extended order cycles. Impact: If a car were to operate without any chips, the most basic consequence would be a loss of intelligence and comfort. Currently, most cars on the market come equipped with a significant degree of intelligent and technological features. Beyond the common multimedia infotainment systems that rely on chips for processing, functions such as auto start-stop, smart keys, lighting control, power windows, electric power steering, power seat adjustment, seat heating, and air conditioning systems all require chips to process electrical signal commands. Over two decades ago, cars entered the era of electronic control, where electronic functions, in most cases, cannot directly control the vehicle. Instead, they rely on chips to issue commands for the car to perform corresponding actions.

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Why is the cylinder head screw of a underbone motorcycle leaking engine oil?

What is the date for tire code 4621?

Can Out-of-Town Used Cars Be Licensed Locally?

Will the car alarm when the engine oil is low?

What is Neutral Gear on a Motorcycle?

What are the differences between 18-inch and 19-inch wheels?

Can Cars Operate Without Chips?

What is the reason for the peeling of a layer of film on car headlights?

What speed can a car reach in third gear?

Why Can't High Beams Be Equipped with Lenses?

What are the reasons for the yellow light on a China V diesel engine?