Technical Comparison

Income Analysis

Take heavy truck’s standard wheel type (22+2(the spare tire)tires) for example:

1.The tire cost reduces

The tested tire is from the brand Michelin 295/80R22.5 (X Multi Z),
According to the change of the depth of tire’s pattern, come the following chart:

2. Fuel consumption reduces

After testing: two vehicles with the same driver, the same route and the same load, take the beginning of April as the dividing point, from January to March before the installation of Yueling’s lightweight commercial aluminum wheel; The average fuel consumption of the two vehicles is 33.52 l / 100km. After the replacement of Yueling’s Lightweight commercial aluminum wheel, the average fuel consumption of the two vehicles from April to June is 32.16 l / 100km, which is 1.36 l / 100km lower than the average consumption before installation

3.The load of trucks increases

The weight of aluminum alloy wheels is 27.3KG, and the weight of steel wheels is 55KG, the reduced weight can be replaced by products’ weight

The modification encyclopedia

Classification of hubs: Wheel hubs can be classified by material: steel wheel hubs, aluminum alloy wheel hubs

Compared with steel wheel, aluminum wheel hub has the following advantages:

1. More energy-saving, lightweight, higher making accuracy, not easy to be deformed when it rotates in a high speed, small inertia resistance, help to improve car’s straightforward driving performance, reduce wheel’s rotation resistance, and consequently reduce oil consumption

2. Safer, the thermal conductivity of aluminum alloy is three times that of steel, the heat dissipation effect is very good, so as to enhance the braking performance, improve the life of tires and brake, effectively guarantee the safety of the car.

3. More comfortable, Cars with alloy wheels generally adopt flat tires with better cushioning and shock absorption performance than ordinary tires, which greatly improves the comfort of the car when it is running on uneven roads or at high speed.

Because of its advantages, aluminum alloy wheel hub has gradually replaced the steel wheel hub, so far, the proportion of aluminum alloy wheel hub in the car application has reached more than 70%.

Classification by production process

Aluminum alloy wheel is currently used in the main production processes: forging, hot die forging, spinning, casting.

Comparison of manufacturing cost ：Forging >Hot forging>Spinning>Casting

Comparison of quality：Forging >Hot forging>Spinning>Casting

Forging wheel hub and hot mold forging can not be popularized because of the high equipment cost, high mold cost, low yield and expensive price. At present, they are mainly used in racing, supercar, and the refitting of high-class sports car.

Although the cost of spinning wheel hub equipment is high, but its mold can be universal, high yield, and the quality can basically achieve the advantages of forging wheel hub and hot mold forging wheel hub. Spinning wheels are gradually be promoted. At present, many main engine factories in Japan have used spinning wheel hub to replace the original low-pressure wheel hub.

Casting wheel hub can be divided into low-pressure casting wheel hub and gravity casting wheel hub. Although the technology of both is obsolete, they have been used to this day because of their low cost.

Comparison of manufacturing costs: low-pressure casting> gravity casting

Quality comparison: low-pressure casting> gravity casting

In low pressure casting, the pressure, temperature and cooling curve of aluminum-water in mold cavity can be controlled better, and the casting quality and casting stability are also better. It is suitable for mass production. At present, most of the main engine factories at home and abroad use low-pressure casting wheels.

Gravity casting is widely used in small batch production because of its low mould cost and short stable production time. At present, the gravity casting wheel hub is used in most of the aftermarket refitted wheel hub at home and abroad.

Wheel structure diagram Terminology about wheel

1. Wheel size: in the case of 18x8.0, 18 refers to a hub with a diameter of 18 inches and a rim width of 8. 0 inches. The diameters and widths here refer to the diameters and widths of the locations where the tyres are installed;

2.PCD value: the diameter of the circle formed by the center of the hub bolt hole. In the case of 5x120, 5 means the number of bolt holes is 5, and 120 means the diameter of the circle in which the bolt hole center is located is 120mm.

3.Center Bore (CB) to ensure that the hub can be installed on the axle, in the case of CB73.1, refers to the diameter of the hub center hole is 73.1mm. If the center hole is smaller than the diameter of the axle, the hub can not be installed on the car. If the center hole is larger than the diameter of the axle, it can be solved by the bushing ring.

4.Geometric centerline: the centerline centered around the rim, which is the most important reference data in the hub. You must refer to this value, including the calculation of the Offset value, the distance between X, and so on.

5.Offset ET: the distance between the hub mounting surface and the geometric centerline. In the case of the ET40, the distance from the hub mounting surface to the geometric centerline is 40 mm. Positive offset if the hub mounting surface is outside the geometric centerline, otherwise negative offset. ET can be understood as the location of the hub relative to the inside and outside of the car. The smaller the et value, the more the hub will protrude in accordance with the vehicle. If the ET is too large, it will cause the tire to rub on the car body, or the spoke will hit the brake. If the ET value is too small, it will cause the hub to protrude out of the eyebrow, or the tire to rub the outer eyebrow.

6.X distance: the maximum distance between the drop surface in the hub and the geometric center line. It is a basis for determining whether hub disc surfaces and calipers will rub or touch each other.

7.There are three kinds of wheel hub surface technology

Painting. That's paint. According to the different paint and painting process, can be divided into silver, black, matte black, gun gray, bright silver, bright black, and so on. It is also the lowest price of the three.

Painting the car surface / side. That is, after painting on the wheel disc or wheel flange part of the processing, spraying a protective transparent paint on the surface. The price is a little higher than the painting.

Electroplating is divided into water electroplating and vacuum electroplating. The color of vacuum plating is more diverse, more good-looking, but the warranty time is generally about one year. Water plating have only a single mirror color, but the shelf life can be up to three years.

Tire: It is a kind of round and circular elastic rubber product assembled on various vehicles or machinery that is usually installed on the metal rim to support the body, cushion the external impact, realize the contact with the road surface and ensure the driving performance of vehicles. Let's take a look at the basics of tyres.

Tire composition

A tire is usually composed of an outer tire, an inner tire, and a pad. Also do not need inner tube, the tire body layer has a good air - tight rubber layer, and needs to be equipped with a special rim. The tire structure of all countries in the world is developing towards tubeless, radial structure, flat (the ratio of tire section height to width is small) and lightweight.

Tyre: it is composed of the tyre body, the buffer layer (or the belt layer), the tread, the side of the tyre and the tyre ring. The section of the tyre can be divided into several separate zones: crown zone, shoulder zone (tread slope), flexion zone (side zone), stiffening zone and ring zone.

Tire dimensions and performance specifications

The dimensions of the tire

The dimensions and specifications of tires are mainly represented by tread width, flat rate and tire bore. The tread width is expressed in millimeters. The flatness ratio refers to the ratio between the tire wall thickness and the tread width. The specific calculation method is wall thickness/tread width x100. The inside diameter of the tire is expressed in inches and is also the diameter of the corresponding hub. Today's car tires are generally radial tires.

The marks of common radial tires are mostly shaped like: 215/70R15. The meanings of these Numbers are: 215 represents the tread width, the unit is mm, the width of the general tire is between 145 -- 285mm, the interval is 10mm; 70 is flat ratio, 70 represents 70%, the flat ratio of general tires in 30%-80%, under normal circumstances, ordinary cars should not use flat tires than > 75%, luxury cars and high-performance sports cars recommended using flat tires < 60%; R is the abbreviation of the English radical, representing the Radial structure of the tire, and 15 is the outer diameter of the rim, and the unit is in inches. If a tire is marked in the shape of a 6.00-12, this indicates that it is not a radial tire, but a skew tire, which is now rare in cars because of its poor safety, load capacity and high-speed stability, and is only used in some low-grade SUVs and heavy goods vehicles.

Some tires also contain other letters or symbols that have a special meaning: "X" for high-pressure tires; "C" stands for "enhanced"; B" stands for skew; "One" means low pressure tire. M and S are abbreviations for Mud and Snow respectively, which means that the tire is suitable for use on Snow, Snow and muddy roads. On some tires, the wall is marked with an arrow or OUTER SIDE, indicating the direction of rotation. If a small umbrella sign is painted on the tire wall, it indicates that the tire is suitable for driving on rainy or slippery roads. The DOT mark indicates that the tire is certified by the U.S. and Canadian Transportation Authorities. The DOT symbol is usually followed by a 4-digit number, and unlike other words, it is not produced by the early mold, but by the later pressure on the tire, such as (0518), which indicates the production date of the tire.

Tire load index

The tire Load Index (also known as Load Index, Load Index), refers to the tire under the specified conditions can bear the maximum Load. Load indicators are expressed numerically, for example, 88 for 560 kg and 93 for 650 kg. If the tire is used in the state of exceeding the load index, it will not only greatly shorten the life of the tire, but also greatly increase the risk of puncture. See the diagram below for details.

Tire speed indicator

The speed grade indicates the maximum speed at which a tire can carry a specified load under specified conditions.

Commonly used speed levels are: Q 160 km/H V 240 km/H R 170 km/H W 270 km/H S 180 km/H Y 300 km/H T 190 km/H H 210 km/H Z ZR faster than 240 km/H, if ZR, such as 40 zr17 P275/93 W, so the highest speed rating (" W "in" 93 W ") of 270 km/hour.

If the tire exceeds the speed level under the state of travel, not only will greatly shorten the life of the tire, but also greatly increase the risk of puncture. See the diagram below for details.

Other tire performance indicators

Other performance indicators of tires are grip, wear coefficient, temperature grade, noise coefficient and so on.

Tire pattern

The automobile relies on the tire to support on the road surface, but the direct contact with the road surface is the tire pattern. The tire not only carries and rolls, but also becomes the power source of driving, braking and steering through the friction force between the tread and the road surface.

The following on the role of the tire pattern, the factors affecting the pattern effect and matters needing attention to do an analysis.

The effect of tire tread

In short, the main role of the tread pattern is to increase the friction between the tread and the road, in order to prevent the wheel from slipping, which is the same as the sole pattern. Under the action of tangential forces (such as driving force, braking force and transverse force) between tread and pavement, tread block can produce greater tangential elastic deformation. With the increase of tangential force, the tangential deformation increases with it, and the "friction effect" of the contact surface is also strengthened, thus inhibiting the tendency of the tread and the road surface to slip or slip. This eliminates to a large extent the defect of the tread less (smooth tread) tire easy to slip, so that the performance of the vehicle related to the friction performance between the tire and the road surface - dynamic performance, braking, steering and driving safety of the normal play has a reliable guarantee. Some studies have shown that the factors that produce friction force between tread and pavement also include the adhesion between the two sides, molecular gravity and the micro-cutting effect of pavement microconvex on tread, etc., but the main role is still the elastic deformation of pattern block.

Effect of pattern

There are many factors which affect the pattern effect, but the main factors which are related to the use of automobile are pattern type and pattern depth.

1）Pattern influence

There are many types of tire pattern, but there are mainly 6 types: common pattern, off-road pattern, mixed pattern, single guide pattern, block pattern and asymmetric pattern.

Plain pattern: Plain pattern is suitable for use on hard pavement. It is divided into longitudinal pattern, transverse pattern and vertical and horizontal pattern concurrently.

A．Circumferential pattern

The common characteristic of longitudinal pattern is that the tread is longitudinal continuous and transverse disconnection, so the tread has large longitudinal stiffness, while the lateral stiffness is small, and the skid resistance capability of the tire is strong transverse and weak longitudinal. This kind of tread tire rolling resistance is small, heat dissipation performance is good, but the tread groove easy to embed gravel. Generally speaking, this pattern is suitable for driving on relatively clean and good hard roads. For example, cars, light and minivans, etc., more choose this pattern.

B．Transverse pattern

The common characteristic of the transverse pattern is that the tread is continuous and broken longitudially, so the tread has large transverse stiffness and small longitudinal stiffness. Therefore, the anti-skid ability of the tire shows a strong longitudinal and weak horizontal, when the car is turning at a high speed, it is easy to sideslip; Tyre rolling resistance is also relatively large, tread wear is more serious. This pattern is suitable for medium or heavy trucks with large traction on general hard roads.

C．Crisscross pattern

This pattern is between the longitudinal pattern and the transverse pattern. In the middle of the tread there is generally a zigzag longitudinal pattern, and in the side near the shoulder of the tread there is a transverse pattern. Come so, the horizontal and horizontal of mesa fights slippery ability quite good. Therefore, this type of pattern tire adaptability, a wide range of applications, it is not only suitable for different hard road, but also suitable for cars and trucks.

Off-road pattern: The common characteristic of off-road pattern is that the pattern groove is wide and deep, and the pattern block grounding area is relatively small (about 40%~60%). When driving on the soft road, a part of the soil will be embedded in the pattern groove, must be embedded in the pattern groove of this part of the soil shear, the tire is likely to appear slippery, therefore, the cross-country pattern of grasping force. According to tests, on muddy roads, the traction of the same type of vehicle using off-road pattern wheel swelling can be up to 1.5 times that of normal pattern.

Cross - country pattern is divided into undirected and directed pattern. Directional pattern has directivity when used. Off-road tread tires are suitable for use on bumpy roads, soft dirt roads and roadless areas. Due to the high contact pressure and rolling resistance of the pattern block, it is not suitable for driving on a good hard road for a long time. Otherwise, will aggravate tire wear, increase fuel consumption, the car running vibration is also more severe.

Mixed pattern: Mixed pattern is a transitional pattern between common pattern and off-road pattern. It is characterized by narrow pattern grooves in the middle of tread with different directions or mainly in longitudinal direction and wide pattern grooves in different directions or mainly in transverse direction on both sides. Such pattern collocation makes the comprehensive performance of mixed pattern good, strong adaptability. It not only ADAPTS to the good hard road surface, also ADAPTS to the gravel road surface, slush road surface and the soft road surface, the adhesion performance is superior to the common pattern, but the wear resistance is slightly inferior. At present, some trucks and all - wheel - drive passenger cars use this type of patterned tires.

Single guide pattern: Single guide pattern is the pattern groove is connected to each other, showing the independent pattern block structure. It has excellent braking performance, excellent drainage performance, excellent stability on rainy days, suitable for high speed driving. However, the tyre must be installed in the same position as the driving direction. Suitable for high speed cars.

Block pattern: the pattern groove is connected to each other, showing an independent pattern block structure. Has superior braking and handling performance, snow and wet road superior handling and stability performance, good drainage performance in rainy days. But its independent pattern block structure, wear resistance is poor. Scope of application: all-weather and snow tires for cars, rear wheels for commercial vehicles.

Asymmetrical pattern: asymmetrical pattern has different tread shapes. Because it increases the pressure of the lateral pattern when turning, it greatly improves the performance of high-speed turning and complements the wear-resisting performance of the lateral pattern. But attention must be paid to the correct orientation of the tires. More suitable for competitive vehicles and high-performance vehicles.

2）Effect of pattern depth

The deeper the pattern is, the greater the elastic deformation of the pattern block, and the rolling resistance formed by the elastic hysteresis loss of the tire will increase accordingly. The deeper pattern is not conducive to the heat dissipation of the tire, so that the tire temperature rise faster, pattern root because of stress and severe punishment and easy to tear, fall off. The pattern is too shallow not only affects its water storage, drainage capacity, easy to produce harmful "water skiing phenomenon", and make smooth tread tires easy to slip disadvantages protruding out, so as to make the aforementioned car performance become worse. Therefore, too deep and too shallow patterns are not good. Objective law is to use in the pattern will become smaller.

Tyre pattern diagram

Cautions for the use of tread pattern

1）Should be based on the use of vehicles often used road conditions and speed to choose a more appropriate pattern tires. For vehicles running at medium speed on the general hard road, trucks and buses should choose transverse pattern or both pattern tires; For often on the highway and good hard road driving vehicles should choose good heat dissipation, transverse stability with strong longitudinal pattern and longitudinal pattern tires.

2）With the increase of the speed, the water between the tread and the road surface will form a water film between the two sides before it can be removed, which will slowly lift the tire and even completely leave the road surface under certain conditions, making the car completely lose control. This phenomenon is known as tyre "water skiing". There are many factors affecting the critical speed of water skiing, but tire pattern pattern and confidence are the main factors. Often on the highway driving car, in the case of conditions, should try to choose anti - water ski tires. It should be noted that this pattern has a directional, do not install the careless.

3）The direction of rotation of a directional tread tire is usually marked by the "arrow" moulded on the side of the tire. If the tire rotates in the direction of the arrow, that is, the "herringbone" pattern tip lands first, it is said to be placed in the direction of the tire and rotating in the opposite direction.

To sum up, the tire pattern is an important link to improve the performance of automobile and ensure driving safety. Accordingly, how correct choose and buy, install and use tire pattern appear very important.

Tyre maintenance

Keep these six tips in mind：

After the purchase of your car's tires, the most important thing is to maintain your car's tires in use. In various parts of the car, the price of tires is relatively expensive, so pay special attention to do a good job in the maintenance of car tires.

1、High speed driving to maintain the distance between vehicles, avoid unnecessary or frequent braking (braking), reduce the damage to the tires, at the same time for their own safety to pay attention to the tread depth of the tires, nearly flat tires because of the friction with the road, long braking distance, do not drive at high speed.

2、The tire load and pressure is a one-to-one correspondence, the load is similar to low pressure, will cause tire damage, often under the overload of use, the life of the tire will reduce 20%-50%; At the same time, the wrong way of loading will also cause uneven tire load, affecting the excessive tire load life.

3、Air pressure is the life of the tire, the tire inflated pressure must conform to the national standard for different kinds of tires, specifications specified by the air pressure. To often check the tire pressure, pressure is too high and insufficient will produce abnormal wear, pattern groove bottom crack, cord broken, curtain layer delay. tire blasting and other damage; If you want to continue driving at high speed, the pressure should be increased by 5%-10% above the standard pressure. At the same time, the inner air will rise due to the temperature rise after the tire runs, and the air cannot be deflated at this time.

4、To timely and appropriately on the vehicle tire transposition (adhere to the first level of vehicle maintenance and secondary maintenance of the tire inspection), to keep the tire wear uniform, extend the service life; Tyres with larger outside diameters should be installed on the outside wheels.

5、Do not use refurbished tires on the front wheels. The front wheel as far as possible to use vertical tire pattern, the rear wheel as far as possible to choose horizontal tire pattern.

6、Tyres worn to wear marks must be replaced.

Tyre manufacturing process

1．Michelin C3M technology

Command+Control+Communication&Manufacture，Integrated command, control, communications and manufacturing systems.

C3M has the following five technical points:①Continuous low temperature mixing；②Press rubber parts directly；③Woven/wound skeleton layer on the forming drum；④Prevulcanized circular tread；⑤Tire electrothermal vulcanization.

The key equipment of C3M is the special knitting machine and extruder. C3M technology is realized by taking the forming drum as the core and rationally configuring the special braiding unit and extruder unit. The special knitting machine braid the jointless annular tire cord layer and belt layer around the forming drum, and wound the steel wire around the forming drum to get the steel wire ring. Extruder continuous low temperature (below 90℃) mixing material, pressure out side, triangular strip and other rubber parts.

2．Continental MMP technology

The full name for MMP：Modular Manufacturing Process；Suggest to translate into：Modular Manufacturing Process

As is known to all, the traditional tire manufacturing process consists of four processes：①Plastic/mixing；②Roll out and roll out；③Molding；④Vulcanization。In the existing tyre factories, most of the above four processes are complete except for the first process which is saved by purchasing the finished product mixing rubber.

MMP breaks the traditional pattern of four complete processes in tire factories and divides the four processes into two parts for operation. The first block includes the first step of the traditional process (plastic/mixing), the second step (calendering and pressing) and the front part of the third step (body forming). The second block includes the back part of the third step of the traditional process (banding layer, upper tread) and the fourth step (vulcanization). The plant that performs the first task is called a "platform", and the plant that performs the second task is called a "satellite plant". The platform is responsible for the production of basic tire components and pre-assembly, while the satellite plant is responsible for the overall assembly and completion of tire manufacturing process and final vulcanization. Typically, a platform can be configured with multiple satellite plants to form a radiation network.

3．Goodyear's Summer IMPACT technology

Integrated Manufacturing Precision Assembly Cellular Technology；Integrated processing precision forming unit technology. "IMPACT" means "IMPACT, IMPACT, IMPACT". Therefore, overseas media in the industry have dubbed IMPACT as "IMPACT", which means new technologies that have an IMPACT on traditional manufacturing technologies.

IMPACT has four elements (also known as four units) : a Hot Former; (2) Improve control technology, improve production efficiency; (3) Automatic material conveying; Unit manufacturing. The above four elements can be used alone or in combination, and no matter one element or the whole system can be closely integrated with the existing tire technological process. The IMPACT will not be as incompatible with existing systems as other new-generation tire manufacturing systems.

4．Pirelli MIRS technology

Full name of MIRS：Modular Integrated Robotized System；

The essence of MIRS is to organize production centering on the forming drum; Multiple groups of extruders with remote control manipulator to achieve direct molding from rubber extrusion to molding drum; The embryo gas - tight layer was used instead of the capsule for vulcanization.

There are only three processes in MIRS: Prefabrication; (2) forming; (3) sulfide. There are several extruders in the prefabrication process. Each extruder is equipped with 1× 1.5m coiling shaft bracket and hanging steel wire or dipping cord roller. The multi-strand steel wire or cord on the rack enters into the right Angle head of the extruder and extrudes together with the rubber material to obtain the reinforcing rubber strip for the downstream process. Molding process has 3 groups of 8 extruders and 3 pairs of remote control manipulator, divided into three stations to operate. The forming drum is collapsible and hollow. The body of the drum is made of 8 pieces of 20mm thick aluminum plate. There are small holes on the drum surface to connect with the drum cavity. The forming drum enters the first station by preheating and rotates around the axis. Extruder to the plastic material out of the forming drum, the manipulator repeatedly roller press plastic material, extruded air, so that the plastic material close to the drum, get the air-tight layer; Since the drum is hot, the gum is prevulcanized. Then the forming drum enters the second station, the second pair of manipulator will be prefabricated production of a variety of reinforcing rubber winding on the forming drum, at the same time the second group of extruders will be plastic material extrusion on the forming drum, manipulator and extruder cross operation, gradually form tire cord layer, tire ring. Then the forming drum enters the third station, and the third pair of manipulator is pasted with prefabricated belt layer. The extruder directly extrudes the isolation glue, the side glue and the tread glue to the forming drum, after compaction and shaping, the complete embryo is obtained. The embryo enters into the vulcanizing process together with the forming drum, and the vulcanizing machine is mounted on the column of the six-station disk transport belt. The first pair of manipulator will not take the embryo of the forming drum into the vulcanizing machine, mold closing, into the forming drum cavity through high-pressure nitrogen, nitrogen through the air hole of the drum wall escape to the drum surface, so that the embryo expansion, from the drum surface and close to the inner wall of the vulcanizing mold, so that the pre-vulcanized embryo gas dense layer actually plays the role of capsule. As with ordinary vulcanization, the mold cavity through steam. After 15 vulcanization, the disk transport belt to the sixth station, the second pair of manipulator mold, tire together with the forming drum out, folding forming drum, get the finished tire. The forming drum is assembled and then returned to the second process for recycling. This completes a production cycle.

5． Digital Rolling Simulation

The so-called digital tire simulation technology refers to the realization of various simulation experimental technologies in the supercomputer by simulating the rotating tire model. Is mainly composed of tire pattern noise simulation, simulated air pressure changes, wire absorption force simulation, rubber formula simulation, abrasion energy distribution simulation of real vehicle driving simulation of gas penetration simulation of tire muddy road, the road environmental simulation technology, such as digital simulation better solved the high speed rotating of tires can't collect the disadvantages of tyre connect ground data, shorten the production cycle tire design.

Famous tire brand profile

Pirelli

Pirelli is the main sponsor of Inter Milan, inter Milan shirt chest of the trademark is Pirelli. Pirelli originated in the late 19th century, is one of the earliest tire manufacturers, it belongs to the sport tires, is also the earliest sponsorship of F1, still sponsorship of WRC. To be honest, pirelli tires are perfect for WRC road conditions, super grip, very strong. Pirelli, like racing friend, should be preferred, the grip is too strong, dare not say pirelli is the best, but could be responsible, said pirelli grip is the best, and necessary racing players, but the premise is, you have to endure the pirelli equally powerful tire noise, tire noise, that kind of feeling can not tell, that pirelli tire dealers don't believe it is noise. Pirelli's price in high-end tires belong to the middle, has been localized, sales are not ideal. There are many supporting vehicles, such as BMW 7 series, Audi A8 and so on. If you don't care about the noise of Pirelli, don't care about its high price positioning, like to drive fast, choose Pirelli right!

Continental

German continental tires, also known as continental tires, were made in the 19th century. European Football matches often see horse brand advertisements, car racing seems not to sponsor much, it seems not to have played F1. Those who say Michelin is comfortable have never used A Horse tire. Comfortable silence is the biggest characteristic of horse brand, but it seems only this one characteristic, horse brand is not wear-resistant, grip is general, not strong, not suitable for the road conditions of our country, the price of imported tires is more realistic, the current Chinese factory has not been covered up, the market performance also depends on the positioning of domestic tires off the line. In terms of supporting, Ma Brand tires are mainly supporting some intermediate models, such as Audi A4 and A6, Mercedes C-Class And E-class, AND BMW 3-series. Some of the high-end SUV supporting the horse brand are Czech, noise is not small. If you want to be comfortable and quiet, and have no requirements for wear, movement and price, horse brand is a good choice.

Dunlop (Sumitomo)

Dunlop, who originated in Britain in the late 19th century and was acquired by Sumitomo In Japan, is the inventor of the inflatable tyre. Dunlop is the second F1 tyre brand, currently second in terms of the number of wins in F1 RACES. He is now a major sponsor of the German Touring Car Masters, A8 Touring Car and Motorbike GP. Dunlop is also a major sponsor of many off-road RACES, as he is the best of all off-road tyres. The biggest characteristic of domestic Dunlup tires is that they have no characteristics (similar to Bridgestone, which will be mentioned below), quiet comfort is not as good as Michelin and Horse, grip is not as good as Pirelli, and they are more neutral tires. As a matter of fact, Dunlop is a pure high-end brand in the international market. It can be seen from the supporting products, such as Audi A8, Mercedes-benz S600, BMW 5 Series X5X3 and Volkswagen Touareg, with high prices. In view of the situation in China, Dunlop has appropriately reduced the positioning of some small tires, so that it can meet the demand of almost all models and the price is relatively appropriate. I once read a comment on Dunlop on the Internet: Dunlop is not the best, but the best cost performance tyre. Dunlop is great if you play with your car once in a while, are comfortable and quiet and don't want to be too expensive.

Since Dunlop is a subsidiary of Sumitomo, Sumitomo's tyres are largely similar to Those of Dunlop.

Goodyear

Dunlap left Formula One in the wake of the death of racer Bernard and was replaced by Goodyear, an American brand that now holds the record for the number of F1 RACES won. The number of sponsored car RACES is not known. Goodyear is a typical American product, only for noise resistance, second only to Pirelli, noise close to Pirelli, not wear, but also easy to wear, the price is dead expensive. There are not many supporting vehicles, such as Audi Q7, Land Rover, domestic made cars, Audi, BMW Brilliance and so on. The price and Michelin is about the same, belong to domestic inside the highest price, quality is still poor, the factory output is small, net is OEM product.

Michelin

Originating in France in the 19th century, Michelin was the inventor of the radial tire. F1 after Goodyear, and now a lot of cars, WRC and so on. Michelin belongs to the comfortable tire, comfortable close to the horse brand, grasps the ground wear-resisting general. Michelin is the world's second-largest by sales, behind Bridgestone. It mainly supports the mid-range products of some top brands, such as BMW 5 Series and Mercedes-benz E-Class And C-Class. Personally, Michelin, which also belongs to the comfort tire, is more suitable for the road conditions in China than the horse brand, which is also the reason for Michelin's success in China. Of course, due to advertising, the price of Michelin is not low in China. The price of imported Michelin is not so low as that of Pirelli, Horse brand and Dunlop. Overall, Michelin is good, and if you approve of its brand, here's a recommendation.

Bridgestone

Bridgestone, a truly Japanese brand, is also the latest and only one of the world's six largest tire brands to start making tires in the 20th century. Currently exclusive sponsorship of F1. Bridgestone is similar to domestic Dunlop. It is neutral and has good performance in all aspects. It is second only to Dunlop in comfort and quiet, and it is the most wear-resistant high-end brand. Well, the price, because of the crazy money spent in F1, it's not cheap, it's cheaper than Michelin and Goodyear. And thanks to its sponsorship of F1, sales are at an all-time high: ahead of Michelin, it is now the world's biggest, and Bridgestone has seen its share of high-end models such as the Audi A8 and Mercedes S-class in the past year. Generally speaking, it is not cost-effective.

Upgrade the advantage of tire hub

Upgrading wheels and tires means to increase the size of wheels and use tires with lower flat rate while the outer diameter of tires remains the same.

The advantages of upgrading wheels and tires are：

1、The overall performance of the vehicle is improved

All the sports-related performance of a car should be realized through wheels and tires, but due to cost reasons and road conditions, the original wheels and tires of a car are far from giving full play to the performance that a car should have. Therefore, for vehicles operating in different road conditions, upgrading wheels and tires suitable for their own road conditions is the most effective way to improve vehicle performance. In good road conditions such as high speed, the actual driving speed of the car can be improved by increasing the wheel hub tire size. In the snow, mountain road and other poor road conditions, by reducing the size of the wheel hub, choose the appropriate pattern of tires to improve the passing of the car.

2、Control stability enhancement

In the case of the same outside diameter, the inner diameter of the tire increases, the tire wall becomes smaller, and the rigidity increases. Tread widens, grounding area increases and driving is more stable. The steering wheel sense is increased, the grip is increased, the overall control of the road surface is strengthened, and the handling stability of medium and high speed is improved.

3、Ability to bend is increased

Due to the increase of tire wall rigidity and the increase of turning support force, the deformation of the tire will be reduced during the turning, the tracking ability of the vehicle will be improved, and the emergency response will be more generous.

4、Acceleration and braking efficiency improved

By upgrading the hub and tire, the tire wall rigidity is increased and the tire deformations during acceleration and braking are reduced, thus allowing power and braking to be transmitted more quickly. At the same time, due to the different rubber, high-performance tires have better grip, braking distance and acceleration time, thus providing a more responsive driving experience.

5、Safety performance improvement

After upgrading the hub and tire, the heat dissipation of the hub tire is improved due to the larger hub size, reducing the chance of puncture. In the event of a flat tire, the amount of deformation of the tire will be reduced and the car will lose control much less. In addition, the hub and tire upgrades increase the vehicle's out-of-control limit, reduce the frequency of stability systems such as ESP, and significantly reduce out-of-control rates in extreme conditions.

6、Aesthetic enhancement

Larger hubs provide more visual impact. After the upgrade, the wheel hub style is more luxurious, beautiful, generous, personality, and has a more rich and beautiful surface treatment than the original factory, such as surface fine car, high bright color, color, color, electroplating, vacuum electroplating, stainless steel edge, decorative plug-ins.

Upgrade the disadvantage of tire hub

1、Fuel consumption increase

Fuel consumption increases slightly as the tyre upgrades increase the area of contact with the ground, but better tyre wall rigidity reduces the energy loss due to tyre deformation. In Japan, retrofitters upgrade hubs and save fuel by reducing the tire's tire width to reduce the area of contact with the ground.

2、Improve the noise

After the upgrade of the tire is generally a relatively large tread pattern and widened tread, which will increase some noise. However, if you choose a high performance brand such as Michelin, Goodyear and Dunlop, it will help to improve the noise.

3、Comfort reduction

Due to the increased rigidity of the tire wall, the feeling of driving will be directly reflected to the passenger, and the riding comfort will also be reduced.

4、Expensive refitting

When upgrading hubs, it is often necessary to upgrade the tires at the same time, so the costs are quite high. However, with the rapid development of the domestic wheel hub tire industry, the market price has gradually become clear. At present, some domestic manufacturers have been planning direct camp, to reduce the cost of hub modification. Yueling is one of them.

Zhejiang Yueling Co., Ltd.
Commonly used rim width and tire tread width corresponding table
Hub tire width (in)	Corresponding to the tread width of the tire
	allow	standard	extremity
5	165	175	185
5.5	175	185	195
6	185	195	205
6.5	195	205	215
7	205	215	225
7.5	215	225	235
8	225	235	245
8.5	235	245	255
9	245	255	265
9.5	265	275	285
10	295	305	315
10.5	305	315	325

How do I upgrade hub tires

Hub upgrade

1、Wheel size

Choose the appropriate hub size. When the wheel hub is increased, the corresponding tire upgrade will be thinner, the service life of the tire will be shortened, and the car will be less comfortable. If the wheel hub is excessively increased, the wheel hub will be less protected by the tire, and the impact force will be absorbed more directly by the wheel hub, so the wheel hub will be more prone to deformation and damage. In addition, due to the increase in the size of the wheel hub, the original braking system will not be able to meet the force generated by the upgraded wheel hub, so the braking performance will be weakened. When the rim is wider, the tires will be wider and fuel consumption will increase. In addition, the front wheel may brush against the body when turning. General wheel hub modification upgrade 1-2 inches is appropriate, some models can also be upgraded to 3 sizes.

2、PCD

The PCD (bolt hole) of the upgraded hub must be the same as that of the original car, otherwise it cannot be loaded. For example, Audi's is 5x112 and BMW's is 5x120

3、OFFSET

ET affects the inside and outside position of the hub during loading. The smaller the ET value is, the more outwardly the hub will be on the car. If it is too small, the hub will be outside the wheel head, or the tire will rub against the outer wheel head. ET is too large and can cause tires to rub against the car or spokes to hit the brakes. In general, the offset ET had better be close to the data of the original car (generally speaking, et-5 of the original car and the original factory is a more appropriate interval from ET+3).

4、CENTER BORE

The center hole of the new wheel hub is generally the same as the original car or larger. If the center hole is larger than the original one, a corresponding bushing ring should be added. The use of bushing ring does not affect the safety of the hub, because the hub center hole is basically not stressed. But if the machining precision of axle sleeve ring is not high enough, it may affect the loading precision of the hub；

5、X distance

The X distance affects whether the hub will touch the calipers when installed. Due to some hub modeling reasons and calipers, the hub may touch the calipers and cannot be installed. At present, there is not an accurate X distance data statistics at home and abroad, so it is generally to try to solve the problem.

6、Bolt and nut

After the hub upgrade, try to use the original bolts/nuts, the original is more guaranteed in quality. But this often makes the original bolt wrench not corresponding; Because the original wheel is a large bolt hole, and the refit wheel is basically a small bolt hole. Therefore, it is better to have a suitable bolt wrench for easy loading and unloading of tires.

Tyre upgrade

To upgrade a tire, you must first know the model of the original tire. The model of the tire contains the tire information. For example, the original tire model is 195/65R15. Where: 195 is the width of the tire in unit mm, 65 is the flat ratio of the tire in unit %, the smaller this value is, the flatter the tire looks, 15 is the diameter of the hub in inches, 1 inch = 25.4 mm.

There are three commonly used methods for calculating tire upgrades：

The first method: direct calculation

Take the tire 195/65R15 as an example

Diameter：195x65%x2+25.4x15＝634.5mm

Perimeter：634.5x3.1416=1993.35mm

To upgrade to 16x6.5 hubs, refer to the Table corresponding to Common Rim Widths and Tread Widths of Tires.

Accordingly, the flat ratio (634.5-16x25.4)/(205*2)=55.6%

Therefore, a more suitable tire is 205/55/R16, with a modified diameter of 205x55%x2+25.4x16 = 631.9mm compared with the original, with an error of -4.1‰, within the 3% allowed modification range.

Perimeter：631.9x3.1416=1985.18mm

The second method: correspondence

This method is not very accurate, it was taught by a customer in Europe, but it needs a lot of wheel hub and tire experience, for example, the original tire is 195/65R15, then it can be upgraded to195/60/R16, 205/55/R16，215/50/R16， 215/45/R17

This method is calculated on the premise of hub tire width. That is, for every 1 inch of upgrade, the flat tire is reduced by 5 or 10 tire widths

In the use of this method should pay attention to the tire specifications, not blindly through the rise and fall calculation.

The third kind: software calculation

At present, hub tyre upgrade has been calculated with software on the network, and Yueling company is also developing a hub upgrade and ordering system for customers.