I copied the following information from the local chronicles of Shanghai. According to the article, the product chain of permanent racing was established in this way: the 1959 permanent 81 racing car (I have seen this kind of car before, and the design of this car is very interesting. Flywheels are installed on both sides of the rear axle hub, one side is the spinning of the road, and the other side is the fixed flywheel. In this case, the road race, training or venue, This is also caused by the original economic shortage! In 1965, SC65 road racing car and SC66 track racing car were developed. It is understood that this model is designed and manufactured by imitating German Diamond racing car, and it is better than SC652 and SC662 racing car introduced in shine on you. In 1986, SC653, SC663, SC651 and SC656 were introduced. In 199, SC654 was introduced, and no new models were introduced. Sports cars Sports cars mainly include racing cars, multi-speed cars, off-road vehicles, mountain bikes and all-terrain vehicles. Racing is divided into road racing and track racing. The wheel diameter is 27 inches. It is characterized by high strength, light weight and flexible riding. In 1958, the state decided to hold the first National Games in 1959, requiring Shanghai to make domestic racing cars that conform to the official competition rules. After receiving this task, Shanghai Bicycle Factory immediately organized forces to design permanent brand 81 road racing cars based on the analysis of international famous brand racing cars, and produced 3 cars in January 1959 and mass production in May. The weight of the car is 14 kg, the frame is made of high-quality seamless steel pipe, the handles, front and rear axle covers, front and rear brakes and other parts are made of aluminum alloy, the transmission parts are made of high-grade alloy steel, and the rear wheels are four-flying. In August 1959, at the first National Games, the Shanghai team won the championship with excellent results by riding the permanent brand 81 road racing car, which filled the gap in domestic racing production. In 1965, Shanghai Bicycle Factory successfully manufactured SC65 and SC66 racing cars. This product is made of unequal-wall seamless steel pipes, including frame, aluminum alloy sprocket crank with claw, front and rear axle covers, pull-type front and rear brakes, pin-connected rims and tubular tires. The spokes are of different diameter structure with thick ends and thin middle. The front axle and brake are equipped with quick release mechanism, external speed change mechanism capable of changing eight speeds and small chain. The self-weight of SC65 road racing car and SC66 track racing car is only 1.6 kg and 8.5 kg, respectively, reaching the level required by international competitions. In 1982, Shanghai Bicycle Factory successfully trial-produced SC652 road racing car and SC662 track racing car, and their weights dropped to 9.5 kg and 7.3 kg respectively. Type 652 has four kinds of frames, Type 662 has three kinds of frames, and each has four kinds of handlebar tubes. The handlebars, rims and pedals are made of aluminum alloy. In 1986, Shanghai Bicycle Factory successfully manufactured SC653, SC663 and SC651, SC656 racing cars according to the size specified by the International Cycling Federation. The car body leans forward, and the internationally popular carbon fiber closed wheels are used. The frame, front fork and other parts are made of double-ended unequal-wall chromium-molybdenum steel, which has high strength, light weight and good resistance and sprint. In 1989, in the 14th Asian Cycling Championship, China athletes won the men's 1-kilometer team time trial by using SC654 road racing. In 199, at the 11th Asian Games, China athletes won the men's 1-kilometer team time trial championship with SC654 racing car. There are 9 varieties of racing cars in Shanghai Bicycle Factory and 5 varieties in Shanghai Bicycle No.3 Factory, all of which reflect the new level of Shanghai bicycle industry. Multi-speed sports cars are between light cars and racing cars. The wheel diameters are 27 inches and 26 inches, and the self-weight is 13.5 to 16 kilograms, which can change various speeds. The SC67 multi-speed sports car manufactured by Shanghai Bicycle Factory has 18 speeds. In 1981, the product was sold to the United States and Canada under the trademark Zhuifeng. In 199, the factory developed 18 kinds of permanent multi-speed sports cars. There are 26 kinds of multi-speed sports cars in Shanghai Bicycle Factory No.3, which are made of aluminum alloy handlebars, pincer brakes, pinless cranks and color painting. Off-road vehicles, also known as BMX vehicles, are motorcycles-like bicycles. In 1983, Shanghai No.4 Bicycle Factory successfully trial-produced YM21 and YM22 off-road vehicles, and in 1986, it successfully manufactured YM26 off-road vehicles. Since 1987, Shanghai Bicycle Factory has developed five kinds of off-road vehicles and exported them to six countries and regions. In 1988, Shanghai No.3 Bicycle Factory also successfully trial-produced YM821 16-inch bicycles. Mountain bikes and all-terrain bikes, also known as MTB and ATB bikes respectively, are successfully designed by absorbing the advantages of racing cars and off-road vehicles. Their car bodies are made of chromium-molybdenum steel, with wide tires and deep lines, thick flower shapes and straight and wide handlebars, which are internationally popular contemporary products. From March, 1986 to January, 1987, Shanghai Bicycle Factory No.4 trial-produced the Feida brand YE61 MTB12-speed mountain bike with cast front fork, double front supports, wide handlebars, wide cross-section pedals and wide tires. In 1987, Shanghai Bicycle Factory trial-produced YE84 all-terrain bike and YE83 mountain bike. In 1989, Shanghai Bicycle Factory No.3 designed 26-inch YE87 12-speed mountain bike and 24-inch YE85 12-speed mountain bike, which were exported to 8 countries and regions.