Relationship between engine speed and vehicle speed

　・In Japanese
Premise knowledge
　・How to calculate tire circumference

Explains how to calculate vehicle speed from engine or motor rotation speed.

■Relationship between engine speed and vehicle speed

as below.

＜Specific example of vehicle speed calculation＞

As an example, calculate the vehicle speed when the engine speed is 6000 rpm and 6th gear.



The relationship between the rotation speed and vehicle speed at each gear stage is as follows.

■Relationship between motor rotation speed and vehicle speed

Electric vehicle do not have transmission gears like engine cars do. Due to the fact that the engine's torque decreases as it rotates at high speeds (see here for details) and the reliability of the engine itself, it can only rotate at around 6,000 to 8,000 rpm at most. The motor rotates at a higher speed than the engine, exceeding 10,000 rpm. The relational expression between motor rotation and vehicle speed can be calculated by setting the transmission gear ratio to 1 for the above expression. The characteristics are as follows.

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