Start designing a bike computer for the power age from scratch. It’s got to offer lots of data at once. It has to offer metrics that are relevant to power. All of the data needs to be accessible easily and quickly. Know that the finished product doesn’t have to contend with wires. Know that it should have a mount that can go on the stem or handlebars. Know that it needs lots of memory. It should also work with both indoor trainers and on rides.
This was the game CycleOps played when they went about designing the Joule. We have to admit that while impressed with all we read it could do, we weren’t sure if we could actually use the thing. Kind of like how parents never figured out how to program a VCR when those devices were new. Our SRM PCV has six lines of data, which we love, but we certainly don’t use all the features the PCV possesses. Part of the problem is having trouble fully understanding the navigation system, another sizable chunk is understanding why we would have a need for some of the screens.
Still, the finished Joule 2.0 is fairly easy to explain on a macro level. This is a unit that works on the ANT+ Sport wireless protocol. It can read heart rate, speed, cadence, power via ANT+ and also measures altitude, and with it gradient and VAM. There are two buttons and a directional joystick that can also be used as a button. It comes with a heart rate monitor strap, but you have to add on everything else. You can choose the power meter you want, not start with the meter and then are married to the head unit. It has a rechargeable lithium-ion battery that can last up to 20 hours on a charge. The memory can store lots of rides, they say 20 hours worth, before you fill up the included micro SD card. The unit is both charged by and hooks up to your computer with a USB cable, the same one you use to hook up a digital camera. You can also buy an external charger or re-purpose an iPod charger that accepts USB cables—both will work faster than plugging into your computer.
There are four main screens: dashboard, reports, intervals, and main. Dashboard is what you first see when you turn on the unit, regardless of which button you press to turn it on. Report is the second screen, accessed by pressing the mode button once. Push another time, and you get intervals. Press one more time to get to main.
Navigation is fairly simple, though not always easy. To move around each screen, you need to nudge the joystick. Sometimes, particularly when wearing thick gloves, nudging wasn’t the easiest as the lack of precision meant either pushing down the stick, which changes the data, or moving it in a direction we didn’t want. The mode and interval buttons, because of their size, were much easier to work. Hold down the interval button for a few seconds and the interval you’re in the midst of becomes the data you see. Hold it down again for a few seconds to get back to the ride total. Hold down the mode button for a few seconds and you pause the ride and are given the option to resume the ride, save the ride and start from zero, or clear the ride. If you accidentally opt to clear, there’s a safety asking if you’re sure you want to clear it.
Initially, the five lines of data on the dashboard, with two separate metrics per line, were a bit overwhelming. Ten streams of data to scan and comprehend. It was hard to focus on anything. After a ride, we started to make more sense of what we were seeing. The top line, in black, always shows the time of day and the battery life indicator (there are four bars in the indicator, each represents five hours of run time). The bottom line, which appears to be highlighted, shows two metrics related to whichever of the six metrics in the middle three lines appears to be highlighted. To us, power and speed are the two most important metrics, so we decided to put current power and current speed on the top line. Of next importance is heart rate and cadence, so we put heart rate under power and cadence under speed. For most of our riding, these four lines are what we want to see most of all. The third line was harder to program because what we want to see depends on what we’re doing. We decided to put normalized power and kilojoules for the final line, though we toggled between kj and distance and time depending on what our particular activity was. Kilojoules is good to see on long rides and races as a reminder to eat. Distance is good when performing longer intervals. Time when we’re doing laps. We generally left the highlighted metric as power so we could see average and maximum power at the bottom while we rode.
One of the nice advances that the Joule puts forth is adding some metrics that have been developed specifically for riding with power. Normalized power is a metric devised by the people behind TrainingPeaks WKO+ software. For those not familiar with it, NP is a sophisticated kind of averaging, which is theoretically what your power would be if you rode steadily rather with the wide variances that are common in cycling. NP can give you a better sense of how hard a ride is than average power. And this is a hint of some of the cool features the Joule includes. They also include other Training Peaks metrics, namely Training Stress Score (points that measure the overall physiological toll of a ride; a solid week of training can be 600-800 TSS) and Intensity Factor (how hard a ride is when measured against threshold; IF of one is riding at threshold), both of which allow you to better analyze your ride while you’re in the middle of it.
Most of the other metrics we rarely used. For example, there’s a zones metric where you can toggle between power zone, average power zone, and heart rate zone. We pretty much know what these are in exact numbers and are usually distracted by the number assigned to the zone. The peak power metric is interesting, but couldn’t figure out how to incorporate it into riding. VAM, rate of vertical ascent in meters per hour, is an interesting one, and we certainly can see the value when doing sustained climbing. However, we did few 10-minute or longer climbs during the test period except when racing. And in a race, we’re looking at the meter as little as possible. Maybe when we’re going well, but when we’re hurting, we’d rather not know.
Having time constantly displayed was information we didn’t want to know. When we’re on a ride, we don’t want to think about the time of day. It’s a siren reminding us there’s a life beyond the ride; riding is best when we can be in the moment. Eventually, we learned to largely tune out the time. Having the battery life indicator present at all times is a good thing. Wouldn’t want to have the Joule die on a ride. However, we never seemed to come even close to using the computer for 20 hours before hooking it up to the home computer.
The Reports mode is likewise a nice feature that we had relatively little use for. Scanning through our screen while riding to see how our ride compares to an average of the past two, four, eight weeks, six months and twelve months, is nothing we’d do while pedaling. However, being able to look at the number of surges of a ride or race does have a place. Particularly when doing a sprint workout on training rides.
The Intervals screen is a good feature, as you can review all your intervals at once. You can see your average power, time, average heart rate, and distance for each interval, including your current interval. This is much easier and quicker to review than the reports screen.
The Main Menu has all the setup features as well as a few others. The setup can be done via the PowerAgent program on your computer or on the unit itself. A useful feature here is the bottom command, find sensors. We used this at the start of a bunch of races. It seems as if all the heart rate signals might have confused the Joule, so it registered nothing until we used the find command. Then, it looks for all the ANT+ devices it already has saved, and then it locked onto our heart rate transmitter.
The history option on the main menu doesn’t seem terribly useful unless you like reviewing old rides on the road. We found ourselves only doing this after races to compare one race to another.
The Workouts option is one that currently only applies to people who want to pair their Joule to a CycleOps PowerBeam trainer or the 400 Pro Indoor cycle. It’s a bit of a drag, as this seems like a great feature when going through some workouts on the road or on rollers. You can design the workouts in PowerAgent and then load them onto the Joule. The people at CycleOps say they should have a fix for this in upcoming firmware updates, but they wouldn’t say when.
Firmware. For many head units, firmware is what can make or break an otherwise good design. CycleOps has been good with firmware updates for their PowerTap computer and they seem to be pretty good with updates for the Joule. The unit we tested is an early production model, one that we received well before CycleOps made the Joule available to the public. As we’ve written before, early adopters sometimes pay a price for their insatiable need to have the latest gee-whizmo device. Initially, our device was a bit glitchy—we figure the Pro’s on Cervélo and BMC probably functioned as beta-testers for the Joule. The font initially used for the numbers was a bit small and hard to read, particularly when trying to read time while thrashing away out of the saddle. This was corrected with a font that is taller and more ovalized. Another problem was that the unit did not read altitude when the barometer determined that the unit was under water. As we live at 40 feet above sea level, barometric pressure readings from a bike computer can vary from 200 feet below to 200 feet above; we did a number of rides where we didn’t get any altitude readings at all. A firmware update fixed this. Because of the memory in the Joule, laptop and desktop computers should read the Joule as an external hard drive when plugged in via a USB cable. We didn’t have an issue with this when we plugged into the Windows Vista side of our Mac computer, but we did have some oddities when plugged into the Mac side running Snow Leopard. The unit didn’t appear as an external hard drive in the drive listing and somehow the unit convinces the computer that it had been unplugged and re-plugged if there’s no uploading or downloading going on. We’re told this is a unique glitch and we’re going to work with them to figure this one out.
Right now, the firmware upgrades have taken care of most of the issues we had with the Joule. We’d like our computer to have an easier time reading the Joule, we’d like a way to manually tell the Joule the starting altitude, and we’d like to have the workouts feature work for road and roller riding. If they can take care of that, we believe the unit would be near perfect.
Software. As any dedicated power user will tell you, interpreting the data via software is almost as important as reading the power on the ride. PowerTap users will have to update their PowerAgent program to version 18.104.22.168 as of this writing. PowerAgent 7.5 is necessary because it can read the Joule while earlier iterations can’t. It also has more metrics. The program still isn’t as flexible or editable as WKO+, but it’s definitely getting better. And, nicely, it gives the user the ability to export data in multiple formats: csv (comma separated values), extended csv, tcx (Garmin), and pwx (Peaksware). There is also automatic uploading of activity files to twitter, TrainingPeaks.com, 2Peak.com, and Web4Trainer.com with the simple check of preferences.
WKO+ users will have to upgrade to 3.0 to work with the resulting exported files. At this moment, you can’t upload the files directly from the Joule to WKO+, though an upgrade in PeaksWare’s Device Agent, a necessary component to 3.0, should be released in a few weeks. For the time we’ve had the Joule, we’ve had to either export the activity file to a folder and then import the file into 3.0, or open a paid account on TrainingPeaks.com. With the latter, your PowerAgent program will automatically send your file to the TrainingPeaks website, which is free for anybody. What you’re paying for is a one-button download that you can do on 3.0 which automatically checks your account on the TrainingPeaks website and then imports it into WKO+ on your computer. The auto-upload/one-button download is much easier than the export/import steps and it also imports altitude info, which as of this writing you can’t do via the export/import method. Going from your computer to the cloud back to your computer seems a bit much for transferring a file, but it does offer nice insurance when traveling—this way you can just load up the files from any computer on the road and then drop them all back into your WKO+ at home.
Hardware. We have to admit that we found the Joule to look a bit bulky on our bike, though the backlighting (which you can leave on all the time; good for indoor and night riding), and battery life probably account for how tall the unit is; all in all, a decent tradeoff. The PowerTap is smaller and more attractive and we like how the SRM is smaller and out in front of our bars. Maybe it’s the years we’ve put in with our SRM, but we’ve come to really like having the numbers further out as we have to look down less in order to view them and it is much easier to view when out of the saddle. Interestingly, the Joule is almost the same size as the PCV, just oriented to portrait instead of landscape. Weight-wise, they both come in at 76g, which is heavier than the smaller, simpler PowerTap (40g). The Joule mount weighs 14g, and with some tugging on the zip ties, the mount feels very secure. A CycleOps speed sensor weighs 15g and has stayed in place on our fork since we first mounted it. Cadence we got off the Quarq crank.
This has gotten long. As a device that informs an activity we do every day, we’ve had plenty of time to play with it and think about it and that’s probably what’s reflected in the length. The Joule represents the future of bike computers, a unit that can work with just about any kind of ANT+ enabled sensor and can show you just about any data stream you have a yen for observing, and memory enough to store lots of rides. Once the firmware and software catches up to where they should be, which we expect to happen soon, the CycleOps Joule 2.0 will be a hard-to-beat on board bike computer.