Power Meter Pedals vs Cranks

Pedals or cranks is the question riders actually ask once they have decided to buy a power meter, and most of the answers online get it wrong by treating it as an accuracy debate. It is not. A ±1% pedal and a ±1% crank arm are both good enough to train on, and the differences between well-made examples of each are smaller than the day-to-day variation in how you feel. The real decision is about four practical things: whether the product will fit your bike, whether it can move to another bike, what it does to your pedal choice, and how much it costs.

The case for pedals

There is no compatibility question. Every road crank in current production uses the same pedal thread. That means a pedal meter fits a 2012 aluminium winter bike and a current Dura-Ace Di2 race bike equally, with no part numbers to match, no crank length to specify when ordering, and no bottom bracket standard to check. For a lot of buyers that alone decides it, because the alternative is an hour of research with a real chance of ordering the wrong thing.

It moves. If you have a trainer bike and an outdoor bike — which describes a large share of indoor riders — a pedal meter is one instrument for both. A crank meter is one instrument for one bike. Over a few seasons that is worth real money, and more importantly it means your indoor and outdoor numbers come from the same device.

Dual-sided is affordable. Pedals already have hardware on both sides of the bike, so measuring both legs costs the maker very little extra. Crank-based meters at comparable money are nearly all single-sided, doubling the left leg. Single vs dual-sided power meters covers what that actually costs you.

Installation is a torque figure.Fitting pedals is a job you can do on a kitchen floor. Garmin's manual specifies 25 ft-lb (34 Nm); Favero's Pro RS manual specifies 30 to 40 Nm. Our how to install a power meter guide walks both formats through.

The case for cranks

It is cheaper. The cheapest credible power meter is a bonded crank arm, not a pedal, and it is not close. If the budget is the binding constraint, the crank format wins outright.

Your pedals stay yours. This is the point most pedal-meter advocates skip. Plenty of riders have settled on a pedal for a reason — Speedplay for the float, SPD for walkable shoes on a gravel bike, a specific stack height for a bike fit. A pedal meter overrides that decision. A crank meter does not touch it.

Coin cells change the ownership experience. A rechargeable pedal needs charging; 4iiii claims up to 800 hours from a CR2032 and SRAM around 200. That is the difference between a device you maintain and a device you forget about, and for long unsupported rides a spare coin cell in a saddle bag beats any battery percentage.

The electronics are better protected. A pedal is the part of a bike most likely to strike a kerb, a rock or the ground in a crash. A crank arm, spindle or spider is inboard and sheltered.

How to decide in one minute

Do you own more than one bike you want power on? If yes, buy pedals. This single question settles the majority of cases, and nothing else on this page outweighs it.

Is your pedal choice settled for a reason? If yes — Speedplay, SPD on a gravel bike, a stack height from a bike fit — buy a crank meter. A power meter is not worth unpicking a working bike fit.

Is price the binding constraint? If yes, buy a bonded crank arm, accept a doubled left-leg figure, and get on with training. A consistent number you own beats a better number you did not buy.

Do you specifically want left/right balance?If yes, buy dual-sided pedals, or Shimano's own dual-sided crankset if your bike is 12-speed Shimano road. Balance is the one data point the cheap crank format cannot give you.

What this is not an argument about

It is not an argument about accuracy. Four of the five picks on this page claim ±1% or ±1.5%, and the differences between them in practice are smaller than the difference between a correctly entered crank length and an incorrect one. The errors that actually ruin power data are user errors: the wrong crank length, a skipped zero-offset, a meter fitted at the wrong torque. How accurate are power meters goes through all of them, and how to calibrate a power meter covers the habit that prevents most of it.

It is also not an argument about whether to buy a power meter at all. If you ride mostly indoors on a smart trainer with measured power, you may not need one yet — smart trainer vs power meter and are power meters worth it are the pages for that question.