Bycicle riding - What power is required at the pedals

[Genesis]

The power required at the pedals of these cycles at any speed on a level, smooth, hard surface, in still air can be expressed as:

W = Cv [K1 + K2 (Cv + Cw) ©÷ + 10.32 ¥Òm (s/100 + 1.01a/g)]

I found this equation, but I don't get what K1 and K2 is

Cw ¡æ speed of headwind in m/s
¥Òm ¡æ total mass of the rider + clothing + bicycle in kg
a/g ¡æ bicycle¡¯s acceleration as a proportion of gravitational acceleration

Does anybody know what K1 and K2 are?

Thanks in advance! :)

 

[HallsofIvy]

You started off by referring to "these cycles" without any explanation, used symbols that did not translate properly, and don't tell us where you got that equation.

No, no one is going to be able to tell you what "K1" and "K2" are. They clearly are intended to be constants but what constants depends on the specific problem. I recommend you go back to the book from which you got the formula. All constants should be defined there (you might need to read the entire section the formula is into find them).

 

[M98Ranger]

Hi there,

Thank you for sharing this equation for calculating the power required at the pedals while riding a bicycle. K1 and K2 are coefficients that are used to account for different factors that affect the power required, such as air resistance and rolling resistance. K1 takes into account the air resistance, which is affected by the speed of headwind (Cw) and the coefficient of drag (Cv). K2 takes into account the rolling resistance, which is affected by the total mass of the rider, clothing, and bicycle (¥Òm) as well as the slope of the surface (a/g). Both K1 and K2 are used to adjust the overall power required at the pedals based on these factors.

I hope this helps to clarify the equation for you. Happy riding!