Pedal based power meters are incredibly popular and for good reason, they are reliable, accurate, and relatively low cost, they can be also be easily swapped between bikes.

Pros

Most manufacturers offer Left only and Dual Leg Options

Left only options can be usually be upgraded to Dual

Power Meter Pedals are easily swapped between bikes

Power Meter Pedals are Relatively low cost

Cons

Power Meter Pedals More easily damaging in Accidents

Most Power Meter Pedals only accept Look Cleats

There’s a lot of debate about whether you need Left only or Dual power Meters.

If you have perfect balance between your left and right legs then you can save a lot of money choosing a single sided Power meter which measures the power of one leg and doubles it to estimate your total power.

Unfortunately most people have a left/right leg imbalance. This could be as little as 5% or as much as 15-20%

This imbalance has also been shown to change depending on factors such as fatigue and effort. As a rule, as effort increases the symmetry improves. This means that the error inherent in a single sided system will vary within a ride and across different rides. (If the error was constant we could adjust for it).

It’s useful to know if you have an imbalance and to correct it through training in the gym, but for ongoing training as an amateur a single pedal may be fine as long as you are aware and can accept the inherent inaccuracy.

To give you an idea of the numbers, if your left leg is 5% down on your right the error will be around 2.5%  or 7.25 Watts at 290 Watts,

Knowing your total power plus/minus 2.5 % may be perfectly acceptable to you if you are aiming for an increase of 10-15% over the next 6 months. Much more than a 5% variance and I would seriously consider dual pedals.

A good option is to hire a set of dual pedals and put in some big miles in a variety of conditions before making your decision based on the results.

Here’s a comparison chart to help you choose your ideal best Power meter pedals

Single (Left Hand) Power Pedals

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Exact Single Assioma UNO Garmin Vector™ 3S PowerTap P1S V2
Manufacturer Look/SRM Favero Electronics Garmin Powertap
Model Exact Single Assioma UNO Garmin Vector™ 3S PowerTap P1S V2
Single or Dual measurement Single Single Single Single
Upgrade to dual pedal No Yes Yes Yes
Generic or Bike Specific Generic Generic Generic Generic
Rechargeable Yes Yes No No
Replaceable Battery Factory Only Factory Only Yes Yes
Battery Life 100 Hours 50 hours 120 hours 60 hours
Battery type Li Ion Li Ion LR44/SR44 (x4) AAA
Charge type Magnetic Magnetic NA NA
Charge Time 3-5 hours NA NA NA
Measures cadence Yes Yes Yes Yes
Measures Imbalance No No No Yes
Pedal Smoothness Yes Yes Yes Yes
Material  Carbon/S.Steel NA NA Forged Aluminum
Weight 155 g 152.4 g 160 g 221 g
Q Factor 54.6 mm 54mm 53mm 53mm
Stack Height 11.9mm 10.5 mm 12.2 mm 14 mm
Cleat LOOK Keo FAVERO & Keo (original). LOOK Keo Powertap
Self Contained or Pod Self Contained Pod Self Contained Self Contained
Trainer Compatibility Zwift NA NA NA
Waterproof IPX7 IP67 IPX7* NA
Temp compensation Passive & Active Active Active Active
Bluetooth Low Energy Yes Yes Yes Yes
Ant+ Yes Yes Yes Yes
Warranty 2 years 2 years 2 years 2 years
Website Website Website Website Website
Typical Price £708.00 £441.00 £499.99 £468.00

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Dual (Left and Right Hand) Power Pedals

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Exact Dual Assioma Duo Garmin Vector™ 3 PowerTap P1 V2
Manufacturer Look/SRM Favero Electronics Garmin Powertap
Model Exact Dual Assioma DUO Garmin Vector™ 3 PowerTap P1 V2
Single or Dual measurement Dual Dual Dual Dual
Upgrade to dual pedal NA NA NA NA
Generic or Bike Specific Generic Generic Generic Generic
Rechargeable Yes Yes No No
Replaceable Battery Factory Only Factory Only Yes Yes
Battery Life 100 Hours 50 hours 120 hours 60 hours
Battery type Li Ion Li Ion LR44/SR44 (x4) AAA
Charge type Magnetic Magnetic NA NA
Charge Time 3-5 hours NA NA NA
Measures cadence Yes Yes Yes Yes
Measures Imbalance Yes Yes Yes Yes
Pedal Smoothness Yes Yes Yes Yes
Material Carbon/S.Steel NA NA Forged Aluminum
Weight 155 g 152.4 g 160 g 221 g
Q Factor 54.6 mm 54mm 53mm 53mm
Stack Height 11.9mm 10.5 mm 12.2 mm 14 mm
Cleat LOOK Keo FAVERO & Keo (original). LOOK Keo Powertap
Self Contained or Pod Self Contained Pod Self Contained Self Contained
Trainer Compatibility Zwift NA NA NA
Waterproof IPX7 IP67 IPX7* NA
Temp compensation Passive & Active Active Active Active
Bluetooth Low Energy Yes Yes Yes Yes
Ant+ Yes Yes Yes Yes
Warranty 2 years 2 years 2 years 2 years
Website Website Website Website Website
Typical Price £1,238.00 £708.00 £849.99 £730.00

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