We’ve spent a couple of months using the Power2max Type S and it’s a very easy unit to install, use and maintain. It measures wattage from the crank spider and accuracy has proved excellent against our control power meter. The cost varies significantly depending on what crankset you choose to pair the Type S with, and while it’s not cheap, it’s at the more affordable end of the spectrum compared to other crank spider power meters like an SRM.
The Type S supercedes what’s now called the ‘Classic’ at the top of the Power2max range and, if you’re familiar with the original, one immediate difference you’ll notice is that the new version looks significantly slicker, having replaced the tacked-on looking triangular battery housing on the crank spider with a slot-in design that makes everything look a lot more compact. You still have the option to choose between a 110mm BCD spider (for 50-34t chainrings) and a standard 130mm BCD spider (for 53-39t chainrings) but the change in design now means that aero chainrings can be used with the Type S, whereas previously they wouldn’t fit over the additional triangle of the Classic.
One other superficial (but also functional) difference is that the Type S comes with a batter indicator LED so you’ll know when it’s nearing time to change. And speaking of the battery, it runs on a CR2450N coin-style battery, slightly chunkier than the CR2032 that you often find in similar devices. One of these should see you through around 400 hours of riding, although that can change according to various factors. The point is that you won’t be changing batteries every week. And even if you ride all day every day (literally, that is, without stopping for sleep or anything) you should only need to replace the battery every two and a bit weeks. Not bad.
If you’re worried about compatibility, it’s not really an issue either. This one is BB86/386 ready, which also means that it’ll work with BB30, PF30 and related frames if you add FSA’s adapters (basically two little aluminium space fillers) into the equation to fill up the gaps. Power2max sell the Type with a number of cranksets and ours came with FSA K-Force Light cranks for €1,260 (around £880). At the top of the range, you can get the Type S with Campagnolo carbon cranks, as used by Movistar team leader and Tour de France runner-up Nairo Quintana, for €1,890, while at the other end the Type S comes with FSA Gossamer cranks for €940, so there’s plenty of variation in terms of cost. Power2Max also sell the crank spider alone in a selection of Rotor, Specialized, SRAM and Cannondale variations for €940 in case you already have cranks from those brands (so you’d only have to change the spider). The best thing to do is to check out the Power2max website to see what’s on offer.
The unit has also shed a little weight since its first incarnation, although it can be tricky to determine because overall weight obviously has to include the crank arms and weight varies depending on which model you choose. Anyway, the new sensor weight (that’s the crank spider without arms, spindle or anything) is 178g for 110BCD and 195g for 130BCD, as opposed to 225g and 264g for the same size in the Classic. That’s a 47g or 69g weight saving, which won’t be the difference between sailing up a climb or slogging, but a good difference considering that the crankset overall is heavier than its non-power meter equivalent anyway due to the addition of the extra bits that measure power (that’s a technical term). The little extra weight is the price you pay for the ability to measure your power output.
Installation is in three parts. The first part is attaching the crank spider to the cranks. You do this by sliding the axle through the hole in the power meter, and locking it into place using the supplied tool. You have to lock it tightly, too, because you don’t want anything coming loose when you’re riding.
Second is installing the chainrings. The unit doesn’t come with rings, unless you’ve used the option during checkout on the website to add some (Power2Max offer Praxis Works or BOR rings at extra cost should you want some). The unit also doesn’t come with chainring bolts, so you’ll need to grab some of them too, just in case your chosen rings don’t have any. Then, it’s the same as installing any other rings on any other spider, really. Manoeuvre the big ring into position over the crank arm and the small ring into position on the back of the spider, insert the bolts, tighten and that’s done.
The final part of the process is installing the cranks onto the frame. The nuances of this will vary according to what bottom bracket and frame you have, but the important thing to know is that the Power2max power meters don’t require you to install a battery like, say, a Quarq. It’s actually pretty helpful because battery installation can be a right pain and occasionally require some improvisation depending on how your frame and crankset sit with each other and the design of your bottom bracket shell.
Once the crankset is installed, you’re pretty much done. There’s no calibration required, and the Type S automatically zeroes itself, which makes things wonderfully easy and means you have very few things to remember before you head out to ride. And as someone who always seems to leave something at home, that’s definitely a bonus.
As an aside, you don’t need a cadence magnet with the Type S, which means if the bottom bracket or chainstays of your bike are slightly unusual, there’s no irritating bodging trying to get the magnet to sit close enough to the unit.
In use, the Type S has a few smart features that make usability that little bit easier. First, the auto zero means that you don’t have to zero the unit manually (although you can calibrate it from head units similar to most power meters). Similarly, if you don’t pedal for two or more seconds during a ride the unit will auto zero itself so it’s effectively constantly self-regulating.
Which chainrings you need don’t affect calibration either. We used our Type S with SRAM Red rings, mostly because they were the only ones we had around that weren’t already on a bike, but in theory you could swap them out for any others and still get the same numbers when you ride.
In terms of temperature, Power2max units are calibrated in a climate-controlled environment. The unit monitors temperature while you ride, and will compensate for any changes in temperature between auto-zeroes.
One other useful feature is that you can change the battery yourself. That might not seem like a revelation now, but in the past with units like SRM you had to send it back to the factory to have the battery changed. Now, changing the battery takes a few minutes and is far easier, even though you’ll probably have to take the cranks off of the bike to do it. Still, much easier than sending the whole thing away.
Wireless communication from the unit is ANT+, meaning it’ll communicate with the vast majority of bike computers on the market (but not the new Polar v650 and m450, which only have Bluetooth Smart).
In testing, not only did the unit perform straight after install (which sounds like a given but you’d be surprised how many other units can be more fiddly and need tweaking), but it gave consistent readings all the way through testing. In the accuracy stakes, it performed well within its +/-2 percent accuracy against my tried and trusted control unit and repeated that ability ride after ride, so although we don’t have the capability of lab testing at RCUK, it passed the comparative testing we could do.
The Type S measures power on both sides – left and right – as opposed to some other units on the market that double a single-sided measurement (Stages or Garmin’s Vector 2S being examples). That means you can have additional metrics like left/right balance on screen should you so wish – although in practice I’ve not found a huge amount of practical use for this as I (fortunately) don’t have a significant imbalance between legs.
Power2max’s Type S power meter is a funny one to judge in some regards. For one, it’s hard to make a call on value for money because although our test unit with FSA K-Force Light cranks is around £887 (depending on the current exchange rate) it’s possible to get cheaper ones (the FSA Gossamer version, for example) or far more expensive ones (like the Campag version). But this one, certainly, is still cheaper than many of its crank spider-based competitors and if you’re after a spider-based unit (there are other types available, like the Stages crank arm unit and Garmin’s pedal-based Vector) then it’s one to consider.
Installation, use and maintenance are very simple which is a huge bonus – especially for anyone new to riding with power – and, if our experience is anything to go by, you’ll almost certainly have no issues getting the unit working and keeping it that way. Just as importantly, accuracy is excellent.
– Easy to install, use and maintain; excellent accuracy
– No cadence magnet needed
– Not cheap, but not prohibitively expensive and the price and can come down if you want a less exalted crankset
– A little bit on the heavy side
– As with all crank spider-based power meters, it’s not as easy as others to move between bikes