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Stages Cycling
Shimano Ultegra R8000 R Power Meter Crank Arm

2 out of 5 stars
2 Reviews

Out of Stock

Don't worry though, we have a lot more Road Cranksets in stock than that.

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Shimano Ultegra R8000 R Power Meter Crank Arm

By now, we're fairly certain you're aware of the benefits of riding with power and its potential to take your training and racing to the next level. Well if you have a Shimano 11-speed drivetrain, especially if it's the latest version that begins with a U, and you've been dabbling with the idea of buying a power meter, we'd suggest you have a look at the Shimano Ultegra R8000 R Gen 3 Power Meter Crank Arm with Chainrings from Stages and start training like a pro. We like this powermeter for many reasons for things like its relatively affordable price point, legendary Stages quality, direct replacement for the R8000 cranks, and its fitment on practically any frame so you can ensure that every metric is accurately measured from clipping in at the start of the ride right up to dismounting the bike at the end. And while dual-sided data junkies may scoff at the fact that power is only measured from the drive side, we find the metrics quantified are more than accurate enough to train properly and become a stronger cyclist.

Providing the powerful power metrics is a pod affixed just in front of the spider on the drive side arm near the spindle, on an otherwise standard Ultegra 8000 crank. What's amazing is how much this little addition helps to take your training to the next level by adding the ability to pinpoint power data and better measure your rides. It utilizes a blend of strain gauges and an accelerometer to gather position and force data 64 times per second and deliver power readings with a claimed +/- 1.5% accuracy that's right in line with what we'd expect from any quality power meter.

For the gram counters out there, the Stages meter adds a minuscule 20 grams to the stock crank arm, which is a tiny concession to gain the massive data tracking and training specificity having a power meter affords. To put it in perspective, that’s most likely less than one swig out of your water bottle. We really appreciate the user-friendliness of its coin cell battery, offering up to 200-hours of battery life. The meter its self is well protected, earning an IPX7 waterproof rating to give you peace of mind during an unexpected rain shower or during bike washes. Other thoughtful details include the active temperature compensation that helps provide more accurate readings when the climate fluctuates and there's no need to continually calibrate the meter with the dropping and rising mercury throughout the ride.


  • Train smarter with a power meter and Ultegra chain rings
  • Power is measured withing +/-1.5% accuracy
  • Active Temperature Compensation maintains accuracy
  • Measure cadence with the internal accelerometer
  • Coin cell battery is easy to replace and offers 200+ hours of life
  • Communicates via Bluetooth Smart and ANT+ wireless protocols
  • Includes drive side crank arm and Ultegra R8000 chainrings
  • Compatible with cranksets that have 10mm of clearance from chainstay
  • Item #SGC001A
Arm Material
Arm Length
165mm, 170mm, 172.5mm, 175mm
Chainring Sizes
50/34t, 52/36t, 53/39t
Bolt Circle Diameter
110mm asym
BB Type
[recommended pressfit] SM-BB72-41B, [recommended threaded] SM-BBR60
Q Factor
Compatible Components
Shimano 11-speed road
Claimed Weight
[power meter] 0.7oz (20g)
Manufacturer Warranty
1 year

Overall Rating

2 based on 2 ratings

Review Summary

1 Stars - 0 reviews
2 Stars - 2 reviews
3 Stars - 0 reviews
4 Stars - 0 reviews
5 Stars - 0 reviews

Fits True To Size

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What do you think about this product?


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2 out of 5 stars

November 27, 2020

Wildly inaccurate vs. other meters

I've put it through the wringer
Size Bought:
5' 5"

The good news is, the right side power meter crank from Stages has been reliable in all kinds of weather. Reliable as in, no power drops or problems connecting. The bad news is, it consistently reads 30 watts higher than my two other power meters (!) 30 watts is nearly two full power zones. It's normal to have some variance between power meters, but 30 watts is ridiculous. I re-calibrate before every ride and crank length is set correctly, but that does not help. New batteries didn't change things either. For comparison, my other two meters are a Stages left side crank meter on a different bike, and my Tacx Neo 2T trainer. Those two power meters are within 5 watts of each other most of the time, stretching to 10 watts sometimes but no more than that. This is what I expect. But 30 watts is such a huge difference that it messes up my power zones when riding specific workouts in TrainingPeaks and Strava. I have to constantly edit my FTP in those apps in order to hit my watt targets during the workout if I'm using this meter, and to get an accurate account of whether I met my workout goals. It's quite annoying for such an expensive meter. Bottom line: I do not recommend buying this meter.

North K
2 out of 5 stars

May 25, 2020

Inconsistent and unrelaible

I've put it through the wringer

The power meter numbers unfortunately jump all over the place, even after you do a zero-reset before each ride. I ended up comparing this product to the Assioma Duo's and a Wahoo Kickr Core unit. The power is comparable at times but drops 25-30% at other times. It seems to have more issues outside for some reason. I did a ride with my friend last weekend and he averaged 40 watts more than me despite two things; I weigh 10mlbs more than him and we were going the exact same speed. Installation is a breeze if you have an ultegra BB or, in my case, a MegaExo. It's a shame it didn't work.

Chris D

Originally reviewed on Backcountry.com