Bolt-On Power

Bolt-On Power

How much? It’s a curious question, one many of us are prone to ask and yet one that another slice prefer not be uttered. I find it curious when I encounter someone who doesn’t measure their cycling by some standard. I suspect that for many of us our taste for data is directly proportional to our ambition. For those cyclists attempting to improve, data is a way to quantify where we are, where we want to be and the distance between the two. A disinterest in numbers suggests that cycling fits in a different place in that rider’s life, that cycling is less a pursuit than a refuge.

While I’ve done those miles, time that I define as recharge, there’s always a piece of me that wants to frame that experience in objective metrics. How long? How far? How fast? It’s true even when I haven’t exerted myself. If you’re one of those who doesn’t need a number to tell you how good a time you had, just hit the back button. For the rest of you, we souls whose curiosity isn’t easily sated, stick with me for a bit.

For the better part of a year I’ve been using Pioneer’s SGY-PM90 power meter. I began with their left crank arm, added the computer and then later added the right crank arm. This, despite the fact that I received a single box with all three. Why? Well I wanted to experience the modular nature of the Pioneer system, a quality that makes the collection of products an actual collection rather than a self-dependent system.

Let’s be real. Spending more than $1000 on something that won’t make your bike lighter or more aero can be a hard sell for many cyclists. And because power has been an expensive number, most of us just do without. That said, the experience of using the Pioneer system has been eye-opening. When I go for very long without wattage, I find that I can underestimate how much wattage I think I am putting out when I’m going hard and yet, oddly enough, it’s easy for me to underestimate how hard I need to go to get any real training benefit. I suspect that would be true for most of us who aren’t training with power data.

The Pioneer power meter, when you use the entire system of both crank arms and the computer, is the only power measuring device I’ve encountered that includes features best utilized while on a trainer. The opportunity to see the force vectors of your pedal stroke is compelling and being able to work on your pedal stroke’s efficiency in real time has few peers, but seriously, to concentrate on pedaling in perfect circles is something most of us shouldn’t be doing out on the road. With your bike clamped in a trainer, you can learn just how balanced (or not) your pedal stroke is, even as you work to pedal in perfect circles.

Consider this: It offers all the major features the Computrainer does, but can also be used out on the road.

I used to think I had a pretty smooth, pretty even pedal stroke. Like I said, I used to believe that. This gizmo poked a zeppelin-sized hole in that fantasy. My left leg is stronger than my right; my imbalance is on the order of 60/40. My right pedal stroke is way heavy on the 2 o’clock to 6 o’clock phase; the left side looks only marginally better. I’ve been aware that I have a leg length discrepancy; this has been an interesting education is some of the practical effects of that difference.

Most folks, I expect, don’t suffer issues like I do, but that doesn’t make this any less useful. Some people don’t want numbers while they ride or even after they ride. I get that. However, many of us—millions of us, judging from Strava—want some sort of accounting of the work we’ve done when we’re out. We like being able to put a number to the question of how hard.

Installation isn’t super-easy; I needed help getting the head unit to recognize both crank arms, but I’ve encountered other devices that caused more hair-pulling. What I do like reporting is that once set up, it’s a no-muss, no-fuss device.

There is one significant drawback to the Pioneer system. They currently only offer three cranks: Ultegra 6800, Dura-Ace 9000 and the new Dura-Ace 9100. I accept that there’s not a Campy-file on the planet that will add a Dura-Ace crank to a Record-built bike; there is a Campy solution, of sorts, and I’ll get to that soon. It’s not going to go over well with SRAM users, either. So unless being matchy-matchy is something completely off your radar, the Shimano-only options do cut down its appeal. Within Shimano, though, you can get virtually any crank length and any chainring combination the company has ever offered.

There’s also one hitch in how this is sold. It makes sense to me that you should be able to buy the left arm, the right arm and then add the computer. Unfortunately, while you can purchase the left crank arm ($559.99 to $629.99), and you can purchase the computer (either the SGX-CA900 for $499.99 or SGX-CA500 for $299.99), the right crank is only available as an upgrade to your existing crank. So yes, you can get the right crank, but you must send in your existing crank to be retrofitted, and that means that you either need to do it during down time of winter (or illness), or you need to have a spare crank. The upgrade is only $579.99. So, while a bit short on convenience, it does allow you to purchase the components on a piece-by-piece basis.

If you purchase everything as a package, the retail is $1499.99 for Dura-Ace (either iteration) and $1299.99 for Ultegra. Compared the the $629.99 for a single Dura-Ace arm ($559.99 for Ultegra), and considering that it doesn’t come with the computer or cheststrap, it makes sense to purchase the components separately and make the investment gradually.

Now, that thing where I mentioned a Campy solution: One other bright spot in Pioneer’s offerings is that you can send in any one of many different left crank arms and even the drive side Campagnolo Potenza crank and have them retrofitted with Pioneer power meters. To retrofit both cranks is $999.99; to retrofit just the left is $499; to retrofit just the drive side as I mentioned before is $579.99. Acceptable left cranks for retrofit include Shimano XTR Trail, XT, 105, FSA SL-K Carbon and Cannondale SI SL2. And beginning in December, all of these cranks will be available aftermarket, not just as retrofits.

Accuracy is often the big battle between the various power meter brands. An accuracy rate of +/- 2 percent is solid enough for anyone who isn’t a 23-year-old Cat. 1 trying to get Jonathan Vaughters’ phone number. Even if you’re an aging guy like me who isn’t likely to ever be as fast as he was, for most of us, there’s room to be faster than we are, and for some of us, that pursuit remains part of the fun of riding. With the Pioneer power meter, you can learn more than Strava would ever tell you.

Final thought: Part carrot, part stick.


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  1. TomInAlbany

    I don’t race. I use heart rate and strava times to monitor my fitness and power.

    I know it’s not as good as a power meter but, for that kind of cash, I can fly my family to Disney. (We can’t go in but…)

  2. Les.B.

    Looks like from the Pioneer site that their computer serves not only as a power meter monitor, but as a general GPS-enabled cycling computer. So this would somewhat justify the price point.

  3. dave

    A power meter only makes you faster if you have a structured training program and use power to calibrate your program.

    Just watching a number as you ride provides the same training benefit as a cycle computer, i.e. none. Its an interesting but useless metric.

    If you are one of those alpha male masters’ cyclists that rides because they love of zones, blocks, spreadsheets, TrainingPeaks and Joe Friel books, by all means get a power meter. For the rest of us its a total waste of money.

    1. Author

      That’s an unfortunate oversimplification. Sure, the biggest gains are to be made using power in periodized training plan, but to say it’s a waste of money otherwise just isn’t true.

  4. Dave

    So for the enthusiast rider, how would power make you faster? Knowing your speed, cadence, or heart rate don’t make you faster absent a structured training plan. Why would power? What makes power different?

    1. Author

      So think of fitness on a continuum. On the left, you’ve got the classic couch potato. At the far right you have Chris Froome. Toward the left end of things you have the guy who rides his beach cruiser most weekends. Toward the right, you’ve got the masters athlete who has a rigidly structured, periodized training plan. There’s a huge distance between beach cruiser dude and masters athlete dude. A speedo will teach you some things. So will a heart rate monitor. But power will tell you, truly, whether you’re working or not. The easiest example I know of is while on a group ride, you might be doing 26 mph on the flat and thinking you’re having a good, hard training ride. In reality, in the draft, you might only be producing 150 watts. Knowing that will spur some riders to get to the front and make an effort to put out 300 watts until they are cross-eyed. Just doing that regularly, even without a periodized training plan, will cause most riders to become stronger. Bottom line: power tells you a lot more about how hard you are working than a speedo or HRM. I hope that helps, but if it doesn’t clarify it enough, feel free to keep asking questions.

    2. Bruce

      Agreed. There isn’t a ride that goes by where I don’t glance down at some point and think “I need to pick it up a bit” or much much less often “wow pushing a bit hard right now”. I don’t follow a structured training plan, but I have no doubt my power meter has made me faster (which is of interest only to me and a few mates), and I simply enjoy knowing what the quantifiable level of power is that my feeble efforts are producing.

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