How to choose the number of teeth for a large sprocket

LSprocketThe number of teeth = the number of teeth of the small sprocket X speed ratio

After determining the number of teeth of the small sprocket and multiplying by the speed ratio, the number of teeth of the large sprocket can be determined.Generally speaking, the number of teeth of the small sprocket should be more than 17 teeth, 21 teeth at high speed, and 12 teeth at low speed, but the number of teeth of the large sprocket should not exceed 120 teeth.Also, when the speed ratio is 1 : 1 or 2 : 1, select a sprocket with a large number of teeth as much as possible.In normal use, please set the speed ratio below 1 : 7, preferably around 1 : 5.