What does the tooth ratio of a bicycle mean?

The tooth ratio is equal to the number of the front plate teeth ÷ the number of the rear flywheel teeth. The role of the bicycle gear and chain transmission system is to convert the energy (horsepower) of the rider into the torque of the tire. The "speed" is determined by the maximum tooth ratio (the largest tooth plate of the front plate corresponds to the smallest tooth plate of the rear flywheel), and the greater the tooth ratio, the faster the speed. For example, the maximum tooth ratio of the general 27-speed mountain bike is "44T before, 11T after, the tooth ratio =4", the driver will turn 4 circles when he steps on a wheel, the fastest speed but the wheel torque is the smallest, and the relative force of the rider must be the largest to maintain the torque required to make the car go forward. "Climbing" with the minimum tooth ratio (the front plate minimum tooth corresponding to the rear flywheel largest tooth), climbing, the driver not only to maintain the car forward, but also to rise height, this time the need to increase torque, in the premise of maintaining the same number of treadle rotation, reduce the tooth ratio to improve tire torque. For example, the minimum tooth ratio of the general 27-speed mountain bike is "22T before, 34T after, the tooth ratio =0.65", and the driver steps on a wheel to turn 0.65, so the driver's physical strength is turned into torque to lift the car for climbing. It should be noted that when the road is wet, high torque will cause the tire to slip, that is, when the torque is greater than the friction on the ground, it can not move forward, and high torque climbing may also warp the lonely wheel.