Bike Cadence Calculator
There is a straightforward relationship between your speed and how fast you are pedaling: discover it with our bike cadence calculator.
Learn the basics of the mechanics of a bike with this short article. We will teach you everything you need to know. Are you wondering:
- What is bike cadence?
- Does the gear ratio affect your cadence?
- Is there a formula for bike cadence?
- How to calculate the bike cadence from speed;
Then you're in the right place. Saddle up!
What is bike cadence?
Bike cadence is nothing but the speed at which you turn your pedals. We measure bike cadence in rotations per minute ().
Since the movement of a bike begins in your legs, the speed at which you turn them is fundamental in understanding the operations of such a marvelous yet simple means of transportation.
Why is cadence important?
Cadence is essential because it determines the power in input to your bike. The power is equal to the product of torque and cadence: the faster you pedal, the higher the force you apply on the pedals, and the higher the power.
There is no specific rule for choosing the right cadence. Usually, the higher the cadence, the better. You can easily see this from the relationship between torque and cadence: a higher cadence allows you to put less force on the pedals, which may save you a bit of soreness after your ride!
However, the right cadence for you depends on many factors: your build, your fitness, and so on. We can help you calculate the frequency in your current set-up: you will have to choose the best value for you!
How do I find bike cadence?
To calculate the bike cadence, you need to know some quantities of your current ride:
- — The number of teeth on the chainring;
- — The number of teeth on the cog;
- — The diameter of the wheel; and
- — The size of your tires.
Do you need a refresh? A chainring is each element of the gear set of the bike. A cog is each gear in the rear gearboxes. The wheel diameter is the diameter of the rigid part of each wheel. Usually it comes in , , or sizes. The thickness of the inflatable part is the last value you need to know.
The formula for the bike cadence is:
where is the speed of the bike.
How do we read this formula for the bike cadence? Follow us in the reasoning!
The bike's speed equals the tangential speed of the tires (approximately, but come on!). We can find the rotational speed of the wheels by dividing the bike's speed by the wheels' circumference:
You can see this quantity in the bike cadence formula above. To find the rotational speed of the crankset, you need to use the gear ratio between the back wheel and the crankset:
where is the gear ratio about which you can learn more at our gear ratio calculator.
Using the bike cadence calculator
Now that you know how to find the bike cadence, calculating it from your bike's speed, it's time to learn how to use our bike cadence calculator.
- Use our bike cadence calculator to find the cadence from your target speed: choose a gear ratio, and find out the best cadence to achieve those km/h.
- Fix the best gear ratio for a given pair of speed and cadence.
At the bottom of our calculator, you can find a table with the cadences relative to various speeds for a given gear ratio and a plot of the same quantity.
More than cadence: bike calculators for every need
Here at Omni, we love bikes: they are clean, silent, fast, and incredibly fun. We ride whenever we can, but we don't stop there! We scienced the hell out of bikes and created a comprehensive set of useful calculators. Visit our:
- Bike cadence and speed calculator;
- Bike speed calculator;
- Bike size calculator; and
- Bike gear calculator;
And if you are still wondering, "should I take the bike?" we've got the answer: it's at our car vs. bike calculator.
FAQ
How do I calculate bike cadence?
To calculate the bike cadence, use the following formula:
cadence = s/((π × (d + 2t)) × ((Nchainring)/(Ncog)))
where we find:
cadence
— The bike cadence;s
— The bike speed;d
— The wheel's diameter;t
— The tire's thickness; andNchainring
andNcog
— The number of teeth in the back and front gears.
What is the bike cadence at 30 km/h, 29" wheels and 3.3 gear ratio ?
About 66 RPM
. We calculate this cadence, equalling about one rotation per second, with the formula:
cadence = s/((π × (d + 2t)) × ((Nchainring)/(Ncog)))
where:
s = 30 km/h
;d = 73.66 cm
;t = 0 cm
— the thickness of the wheel is included in the previous quantity;Nchainring = 36
; andNcog = 11
.
How are bike speed and cadence related?
Bike cadence and speed are related since the speed at which you turn the pedals affects the rotational speed of the tires. To mediate between these quantities, we have the gear ratio (that allows you to pedal faster but with less effort, or vice versa).
The bike's speed depends on the tires' size: the bigger they are, the faster you can go.
What is the ideal average bike cadence?
It depends on your fitness and purpose, but on average, 60-80 RPM should suffice for your non-professional rides.
With a bit of training, you'll be able to pump those numbers up, while on a Sunday cooldown ride, you may prefer pedaling at a lower, more comfortable cadence. In general, the ideal cadence is the one that makes you feel good and doesn't strain you!