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Stages Cycling fires up two-sided left/right power meters

Written by Tyler Benedict Aug 28, 2017 11:30 a.m. ET

Stages Power LR power meter measures separate left and right leg power

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So, according to their testing and feedback with Team Sky (who’s won two Tours de France on this setup), Stages says you may not actually need independent left-right power measurement. But now they’re offering it, because we want it anyway.

The new Stages Power LR puts separate sensors on both crank arms, starting with the latest Shimano Dura-Ace 9100 and Ultegra R8000 cranksets. The two sensors provide independent measurements of positive and negative forces on each crank arm, and when paired via ANT+ provides real time pedaling dynamics info. That means Pedaling Smoothness (what percentage of your pedal stroke is actually applying power to the pedals) and Torque Effectiveness (how much of your power is being used for forward propulsion) figures.

Like the original single-sided unit they launched with, these are waterproof, have a built-in cadence sensor, and transmit via ANT+ and Bluetooth. It’ll work with their Dash cycling computer and Link app, which handles wireless updates, or any other ANT+/BTLE compatible head unit. The Dura-Ace model will ship preinstalled on the crankset for $1,299 (€1,399) and the Ultegra crankset is $999 (€1,099). Both available this fall. Weight for the power meter parts is a mere 35g.

Stages says for most riders, seeing left-leg-only power data is enough to provide an accurate picture of their total output. But, for riders that have a known imbalance, are recovering from injury, or just really want to see the full picture, now they have an option to compete with Pioneer and everyone else.

StagesCycling.com

Tyler Benedict

11,186 articles

Tyler Benedict is the Founder of Bikerumor.com. He has been writing about the latest bikes, components, and cycling technology for almost two decades. Prior to that, Tyler launched and built multiple sports nutrition brands and consumer goods companies, mostly as an excuse to travel to killer riding locations throughout North America.

Based in North Carolina, Tyler loves family adventure travel and is always on the lookout for the next shiny new part to make his bikes faster and lighter.

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PabloE432

6 years ago

Wow their pricing. How can they make any money being so far off the market? Is it just the Shimano OEM look or what?

Chader

6 years ago

Reply to PabloE432

What are you comparing against?

It seems roughly similar to the crank based Pioneer and 4iiii dual power systems for two examples.

It is also similar to the dual measurement pedal options from PowerTap, Garmin with Favero coming in a bit cheaper than all.

Robin

6 years ago

Reply to Chader

They are expensive compared to many of the Power2Max and Quarq options, as well as PowerTap’s hub options.

Chader

6 years ago

Reply to Robin

Got it. So for comparison, a consideration is whether the other options offer Left/Right power data.

I know the PowerTap is kinda dual, but kinda single. You actually measure power from both legs (unlike a single sided arm solution like Stages), but it is not possible to segregate the data to L/R balance since it is on the hub.

I don’t know much about the P2M or Q ones, but I seem to remember they are similar to the PT Hub in that they don’t generally segregate the data to L/R balance.

However, I seem to remember hearing that the new DZero may attempt to calculate a differential based on estimated crank position (via the accelerometer) and the related power measured.

That type of data may not be valuable to all users, but it will be important to some and is a reasonable justification for the price differences.

Robin

6 years ago

Reply to Chader

Has anyone yet demonstrated a benefit to knowing power balance?

Chader

6 years ago

Reply to Robin

There are multiple possible uses. Analysis to identify (and then potentially correct) significant imbalances. These can come from injuries, general fitness (or lack), physical size differences (leg length) and other possible issues.

It’s not likely necessary for many users, but sometimes you never know until you have the information to read in the first place.

Here is some more detailed info and use cases:
http://www.hunterallenpowerblog.com/2015/11/balance-introduction-to-leftright-power.html

https://www.trainingpeaks.com/blog/diagnosing-correcting-pedaling-asymmetry-using-wko4/

carlos

6 years ago

Reply to Robin

I had a mysterious imbalance at lower power that vanished above threshold. Turned out one of my cleats was loose. Hooray for power balance!

Robin

6 years ago

Reply to Chader

Chader, my impression is that the power meter market is being driven by cost, judging by the direction that prices of gone in the last few years and by the prices on a lot the new players in the power meter market.

aeroB

6 years ago

“That means Pedaling Smoothness (what percentage of your pedal stroke is actually applying power to the pedals) and Torque Effectiveness (how much of your power is being used for forward propulsion) figures.”

Pedaling smoothness is the ratio of average torque to maximum torque in a pedaling rotation, not % applying power (basically described torque effectiveness twice). This is why it’s typically quite low (20-30%) compared to torque effectiveness.

tyler

6 years ago

Tour*s* de France 🙂

Wiscomark

6 years ago

Reply to tyler

Seriously, how can a cycling publication get this wrong? You aren’t touring two “Frances”, you’re taking multiple tours of France.

Chris

6 years ago

Reply to Wiscomark

“Seriously, how can a cycling publication get this wrong?”

I guess we’ll just have to wait for the formal inquiry is finished and then the press conference to find out. Stay strong in the meanwhile. We’ll get through this.

Admin

Zach Overholt

6 years ago

Reply to Wiscomark

Thanks for pointing that out. The brain does funny things while jet lagged after 24 hours of travel and writing stories in the car on the way to Eurobike so we can continue our coverage of products like this. Fixed.

Collin Snyder

6 years ago

P2M and Quarq both use a estimation for L/R balance. Its not a true dual sided like this, the 4iiii, Pioneer, and the different pedal solutions. That being said. with a P2M setup, it says for me 44/56 for L/R balance. If that is true, then a stages would be reading about 8% lower than alternative solutions. If you only have one powermeter, it doesn’t matter, however, if you have multiple bikes with multiple powermeters, the measurement method becomes important.

For a comparison, that’s like having a scale in your bedroom that you weigh yourself in the morning reads 5lbs higher then the one in the bathroom that you weigh yourself at night and getting discouraged why you gained 5lbs overnight. Why are there crumbs on the bed and my face is covered in peanut butter?

greg

6 years ago

Reply to Collin Snyder

Because Todd is secretly sabotaging you through an elaborate hypnotic ritual, which has you visiting your pantry every night, of course.

Martin

6 years ago

Is it still possible to move just the left arm over to a non-stages right arm and use it as a single leg meter there? So you can have dual on your main bike, but left leg only on the occational ride on a spare bike?

Jim Jones

6 years ago

Oh good, now there will be 2 sides that don’t deliver a strong or consistent signal to your head-unit. Now we’ll also have two batteries to worry about draining and needing to be replaced multiple times a year.