GEN 3 Stages Power L | ULTEGRA R8000

Kind of pricy, but in line with other power meters. I'm sure as they catch on the price will drop. I had some problems pairing with my Wahoo Fitness ELEMNT bolt. The unit wouldn't calibrate and I would have to have the Bolt "forget" the sensor and rediscover it. This has been corrected with the latest firmware update, BOLT WB15-2659 - 15 April, 2019 and hasn't been an issue since. Had some problem getting the battery cover on correctly at first (it isn't obvious), so for the first few rides the sensor kept losing connection to the cyclometer, but that's operator error.New to using power to track workouts. This review is after about a month of riding with the sensor, but I've been riding for 40 years now. I'm certain that for my training goals and ability it is very much overkill. That said I'm a firm believer in "What gets measured gets managed," so for me more data is better. The main thing this has done is help me to remove the focus on MPH and pay more attention to how hard I'm working. We all know that having a nice strong tail wind will make it appear that you've had a great workout when reality is you hardly broke a sweat, or that a headwind can be discouraging when you fight it all day and the log doesn't show it. Well, now it does. The way I've been using it is to try to maintain Wattage over a ride instead of cycling between mashing down and spinning. It helps to have Di2 shifters to quickly dial in the right cadence and power for any given situation. This has led to some interesting changes in some often-ridden roads just in the first month. I now will usually pedal in a high gear on gradual downhill runs that I would normally would have coasted down before, for example. I've also noticed that my heart rate doesn't necessarily track effort as well as I thought.Overall, I'd give it 5 stars, especially after the cyclometer firmware upgrade, but taking a star off for the expense. Perhaps they could offer a "core charge" for the old crank arms to get some credit back? After all, I now have a worthless Ultegra left crank arm sitting in my garage.

Summary:Updated 7/13/19I've had this for a couple months, and experienced dropouts when climbing out of the saddle. I tried a bunch of things (below), but nothing worked. I opened a ticket with Stages support, and the eventual resolution was that, despite the published lower bound on cadence being 20, the effective lower bound for me is around 40. When I'm out of the saddle, on steeper sections (11+%), my cadence can drop, and the bursty (probably more like stomping) nature of my pedaling causes the arm to miss revolutions. Unlike other PM crank arms, Stages does away with a cadence magnet, and uses an inertial system to determine cadence. My pedaling "style", under high load, messes that up, and it misses revolutions. If I drop a gear, and keep my revs above 40, there is no issue. I suspect I would not have this issue if it used a cadence magnet system, as my cadence is never getting close to 20. I still give it 4 stars, but note that there are conditions under which it doesn't perform as expected.Original text:I was pretty concerned abut dropouts as the gen 1 and 2 stages units had a reputation for dropping connections. Gen 3 is supposed to be much better, but I was watching for issues before my return period was up. It has been great so far, paired with a Garmin 520, which a lot of people criticize as a combination. There was one ride, up a canyon, where the power reading would consistently drop to 0. Coincidentally, I was always out of the saddle on this section. I *know* I wasn't making enough power to give the unit fits. Eventually, I figured out that the head unit was losing the satellites (doubtless blocked by my huffing and puffing torso), thinking I had stopped moving, and pausing the head unit. With no speed to report, it couldn't figure out power. Mildly annoying, and the wheel speed sensor was still paired and active. I'm going to shut off the auto pause feature the next time, but this may not help.Update 6-20-19:Well, I've tried a number of things, one at a time, and none have really fixed the issue:Updating the Garmin Firmware from 3.0 to 4.2. The release notes said it fixed power meter dropouts, and it might have reduced the issue, but didn't eliminate it.Changing the datapoint collection from "smart" to 1/sec. No change.Turning off the phone connection on the garmin. No change.Turning off my phone completely. No change.The Stages is already at the latest firmware revision.The issue still only happens when I'm out of the saddle, and not all the time. The closer my upper body gets to the Garmin, the more likely a dropout. The only remaining bit of electronics that might be emitting interference I have in my camelbak are my car key fob. I guess I can move that to my saddle bag.Update 7/10/19I have tried multiple head units, at the same time, in different locations, and they both show dropouts at the same times. I opened a ticket with Stages support, and they looked at the .fit files from both systems. They tell me that the published lower bound on cadence is "approximate", and with less smooth pedaling styles, the arm can miss revolutions. Below 40 RPM, this can result in apparent cadence of less than 1 rev/3 sec (20 RPM), and head units interpret this as 0. Stages support tells me that a LR (vs. an L), would be no different, as only the left crank arm reports cadence information.

Good accuracy, easy install, good battery life, but irritating lag. It takes 6 seconds from applying force to pedals to get a reading out, and 6 seconds again from stopping pedalling to reading 0. When in a more steady-state case, there is about a 3 second lag after a significant power change, such as a sudden sprint, is reflected in power and cadence readings. No idea why this is. Not the end of the world, just irritating.

The GEN3 Stages Powermeter Ultegra R8000 left sensor only, has changed the way I am training for cycling. The product is very well finished, and if you follow the recommended settings for your cycling computer/GPS you should have no issues with it. No spikes, robust and coherent filtered signals are just some enhancing features of this device. If you want to have pedal smoothness or balance you should by the crank side as well (right side sensor). But, at least for my goals, there is no need for that. You should be able to perform any power based training thoroughly.

Yesterday, was my first road test using a power meter. The ride was with an amazing fast/strong group. At the start of a long climb I working to keep with the leaders and was putting out more wattage then I could sustain. The power meter allowed me to see the over exertion before my body started to feel it/show it. Next week I will control my wattage in the start so I could maintain a more steady output over the whole ride. My hope is to start the climb with less output and makeup ground towards the end of the hill and finish the whole ride stronger/faster overall.I also like the extra information to gauge the effectiveness of my training and fitness levels.

I think this would be a great power meter for a traditional head unit style bike computer, but both the ANT and BLE signals are too weak to work with a garmin watch (mine is a fenix. 5s). Tons of drops. I thought the generation 3 was supposed to resolve this problem, but no dice.