The wheel is one of the four components of racing roller skates: the main difference between the wheel of racing roller skates and other roller skates lies in its large diameter, high hardness and pointed wheel. 1, materials The wheels of roller skates are all made of high-quality resin except low-grade practice shoes. There are many articles about the benefits of using resin wheels, so I won't talk about them here. 2. Diameter The wheel diameter of racing roller skates is the largest among all roller skates. At present, the wheel diameter of competition level is stable at 80 mm, and 100 mm wheel is used for racing roller skates and downhill roller skates. I'll talk to you later. The advantage of big ship mainly lies in its good speed storage performance. No matter what kind of field is absolutely flat, there will be large and small obstacles, which will reduce the sliding speed of skaters. This problem is more prominent in road races. At this time, the larger the diameter of the wheel used by the skater, the smaller the impact and the better the speed saving performance. 3. Hardness The hardness of the wheel of racing roller skates is relatively hard in all kinds of roller skates. This index is usually represented by A. The higher the label, the harder the wheel is, the less elastic it is, the worse its vibration absorption ability, the smaller its deformation when stressed, the higher its ice-pedaling efficiency and the worse its grip ability. The hardness of racing wheels is usually between 82 and 93a. 4. The wheels are very sharp, the contact area is small, and the resistance is small, but higher sliding technology is needed. Choice of wheels: to talk about this problem, we must first talk about the type of competition. The competition determines the venue and the requirements for wheels. At present, there are four kinds of races: track race, road race, marathon and downhill race, which means to hold races in closed roller skating venues. International standard venues are all special competition venues with ramps in an area with a perimeter of 200 meters, such as the roller skating rink of Beijing Workers Stadium and the home of Shanghai avant-garde team in Jinshan District. In order to facilitate popularization, competitions are also allowed in venues that do not meet international standards. For example, the National Roller Skating Championship was held in the venue of Zhejiang Armed Police Lion150m long. Most of these sites are terrazzo floors, which are very smooth. When there is a ramp, it is much easier to do curve movements and dare to accelerate. Indoor competition is also a form of venue competition. There are usually no ramps, but the venues are mostly wooden floors and plastic floors, which are the smoothest of all venues and have high technical requirements for bends. Road race refers to the race held on the highway. Sometimes the venue is not closed, even if the closed perimeter is usually very long, the requirements for athletes' cornering skills are greatly reduced. The site is generally rough and often goes up and down. In the past, professional speed skating teams in China only focused on track events, which was related to the candidates of the national team and the Asian speed skating championships. With the inclusion of road speed skating in the Second National Games, I believe that professional teams will pay more attention to road races. The marathon here refers to the long-distance speed skating competition held on the expressway, and the distance is usually 2 1000, 42 195, 50000, 84390, 100000 meters, etc. This is the most popular competition in the world, mainly because it does not need a special venue, and it is easy to organize and does not need complicated referee work. Many players, especially many fans, can participate in the competition at the same time. This kind of competition has a broad foundation in the world and can bring considerable economic benefits to the organizers, because the number of participants usually exceeds 1000, for example, the Berlin Marathon reaches 6,000, and the cost per participant is about RMB 200 yuan. The venue conditions are the same as road races. Downhill race, sprinting from a height, is an extreme sport. What kind of wheel do you want to choose depends on what kind of race you want to participate in: if you mainly participate in track races, you must choose hard wheels, usually 85A. The track field is flat and there is almost no vibration. At the same time, when you have enough skills, especially in track races with ramps, you are unlikely to slip. At this time, the advantages of small deformation, small resistance, small contact area, small resistance and high speed of the hard wheel will be brought into play. If you mainly participate in track events, you must choose a soft wheel, usually 78-82A, which is the hardness commonly used in overshoes introduced by major manufacturers. The venue conditions of road races have changed greatly. One site may be much smoother than another, and the ground in different parts of the same site is also different. Usually, professional athletes have multiple sets of wheels. Through trial skating, we investigated the whole road section to determine what hardness wheels to use in the race. The flatter the site, the harder the wheels can be used, and the ground is very uneven, especially when there is a' washboard road', which causes great vibration when sliding. Generally, soft wheels are used, which can not only absorb shock but also have good grip on the ground. The requirements for wheels in marathon are basically the same as those in road race. If you want to use a set of wheels for all occasions, please use 84A. When selecting wheels, it should be noted that the dimensions of bearing 608 and bearing 688 are different, so wheels cannot be universal and must be matched. Price: Unfortunately, as a bearing racing major, you get what you pay for. The following prices are international market prices, which are for reference only, because there are many manufacturers, and the prices often change: $ 2-3 per practice wheel depends on the manufacturer, $ 4-8 per competition wheel depends on the manufacturer, and $ 8- 12 per light competition wheel and rain wheel depends on the grade and manufacturer. Main manufacturers: Compared with other products, there are the least manufacturers of wheels. Because it is necessary to have a strong chemical production capacity to produce competitive products, many roller skating enthusiasts order from professional wheel manufacturers through OEM, and then put their own trademarks on them. At present, the main manufacturers are HYPER, kryptonics, labeda, Kopp and other development directions: the main development direction of wheels is weight reduction. At present, roller skates generally weigh 300-400g, bearings 240g (20 bearings 608), 70-80g (20 bearings 688), frame180-240g, and others 25g (5 bearing washers, 2 fixing screws, etc. ) Ordinary 80mm diameter wheels, each weighing 450g. This can reduce the physical consumption of athletes, and at the same time, it is powerful in the completion of tactical actions such as starting, sudden starting and overtaking. Tactics is the core of high-level racing roller skating. The main measures to reduce weight: 1 is to use new resin to reduce weight on the premise of ensuring performance; 2. Change the cross-sectional shape; 3. On the premise of ensuring the performance, the hub is added to make the resin layer thinner and reduce the weight; 4. It is equipped with miniature bearings, usually 688. For example, XTRA LITE ALU, a new racing wheel adopted by Rollerblade Company, is only 18 to 2 1 mm thick, which is far lower than ordinary racing wheels. At the same time, aluminum alloy wheels are used to reduce weight and ensure strength, and miniature bearings are used. It is said to be 20% lighter than the lightest wheel on the market. However, according to my estimation, because the wheels are thin, I'm afraid there is a high requirement for sliding technology, and because the resin layer is thin, I'm afraid the service life is short. Hyper's assault series wheels will be reduced to 81g. Special wheel: 1 conti-rollen is a wheel specially made for road races, made of rubber, and used for rainy days and wet ground. 2 Double-density wheels, such as' Allez dual densty' wheel of Krypton, have high inner hardness and low outer hardness. Their intention is to use the inner side of the wheel to push the ice to slide, give full play to the advantages of the hard wheel, use the outer side of the wheel to bend, and use the advantages of the soft wheel to improve the cornering performance. This wheel is specially designed for track. In practice, it is found that the effect of this method is average, because the density inside and outside the wheel is not much different, and athletes must master the corresponding technical movements in order to give full play to the advantages of this wheel. Finally: 1 There are few domestic qualified racing wheels. The main problems are nonstandard geometric dimensions, inconsistent centerline when sliding, bad foot feeling and many wheels are not wear-resistant. Actually, 80 mm wheels are not easy to buy. It is recommended to buy two sets of wheels for training and competition. Many fans in the world also use cheap training wheels for training. 3 When the wheels of the competition shoes are eccentric, you need to switch left and right. The left 1 wheel (left 1) is changed to right 3, left 2 to right 4, left 3 to right 5, left 4 to right 1, left 5 to right 2, and vice versa.