Proper crank arm spacing?

Asked by: Mike Workman

How long should your crank arms be?

The crank length represents the distance between the centre of the bottom bracket and the centre of the pedal axis. The most common lengths are 170, 172.5 and 175 mm, but it is possible to find cranks between 165 and 180 mm in the market.

What’s the difference between 170mm and 175mm cranks?

Still though, the difference between 170 mm and 175mm is less than 3% and leg lengths of bike riders vary by far more than that. There is a school of thought, particularly in the United States, which suggests that crank length should be proportionate to leg length.

How do you measure crank arms?

How to measure crank length? Crank length is measured from the centre of the bottom bracket axle to the centre of the pedal axle. If you’re not sure what length the cranks on your bike are, the quickest way of finding out is typically to just look at the backside of your cranks, just below the pedal axle.

Are longer crank arms better?

‘The research evidence is clear: crank length makes no difference to power on the road – track is slightly different – unless you go as short as 80mm or as long as 320mm. And as a bike fitter and physiotherapist, I’ve never had a reason to go bigger.

Does crank length really matter?

Crank length can be used as a tool to improve fit related issues impacting comfort, power, and aerodynamics. Moving to a shorter crank can improve: Comfort: A shorter crank length reduces range of motion at the knee (extension and flexion), hips, and low back.

Are shorter cranks better for knees?

In other words, a shorter crank does give you less leverage, but that shorter crank arm allows your downstroke to start where your body can create more power. This (according to the Canfields) produces more power and (according to the study cited below) is better for your knees and hips.

Why are shorter cranks better?

They allow more fluid, comfortable pedalling. They can reduce or eliminate lower back, hip and knee pain. For triathletes the transition from cycling to running becomes easier. Shorter cranks can even make your saddle comfier.

What crank length do the pros use?

Quote from video: This formula assumes that the crank length is around nine point seven percent of our height.

Are longer cranks better for climbing?

2. Shorter cranks are easier to spin and thus better for acceleration and quickness, relative to something longer. Tradition always dictated that track riders used shorter cranks, as their riding style required those characteristics.

What do longer crank arms do?

So if you do end up changing crankarm lengths, it will change your gearing as well. The relative jumps between gears stay the same, but the overall range will feel slightly easier to pedal, or smaller, with shorter cranks and harder with longer ones.

Does crank length affect power reading?

If your crank length is not 172.5 mm however, your power will be off. You could expect a power difference of about 1% based on the difference in crank length. So if your crank arms are not 172.5 mm, you will want to set the correct crank arm length.

Does crank length affect gearing?

Many folks are unaware that your bike’s crank length has a significant effect on its overall gearing.

Do you lose power with shorter cranks?

Based on the results of studies, as listed below, there is no difference in maximal power with slightly shorter cranks and you will be able to reach maximal power quicker with the 170mm cranks, but because your cadence will be higher (which may be beneficial in a hilly area) with shorter cranks you may fatigue more

Are bigger cranks faster?

Then, longer cranks allow a rider to develop more speed than shorter cranks, even when the difference is as little as 2mm.

What chainring should I use?

Quote from video: Похожие запросы

What do shorter crank arms do?

Going to a shorter crank will allow you to ride at a lower back angle which minimizes frontal surface area improving aerodynamics. It can be frustrating to know that there are many available crank options that would work for an athlete.

Does crank length affect power?

Folk lore suggests that crank length has a huge effect on the power that you can generate, or the cadence that you’re able to ride at. Namely, the general view is that shorter cranks allow you to spin and accelerate quicker but at the cost of high torque or power.

What is the best crank arm length for MTB?

There is no magic formula for determining a rider’s perfect crank length, but Buchanan uses a simple rule. “Whether talking biomechanics or simple functionality while riding, I wouldn’t recommend many people under [six feet tall] ride a 175mm crank on their mountain bike.”

Does crank length affect power reading?

If your crank length is not 172.5 mm however, your power will be off. You could expect a power difference of about 1% based on the difference in crank length. So if your crank arms are not 172.5 mm, you will want to set the correct crank arm length.

Why are shorter cranks better?

They allow more fluid, comfortable pedalling. They can reduce or eliminate lower back, hip and knee pain. For triathletes the transition from cycling to running becomes easier. Shorter cranks can even make your saddle comfier.

What crank length do the pros use?

Quote from video: This formula assumes that the crank length is around nine point seven percent of our height.