iBike Gen III Aero First Impressions

I was looking at different power meter options last week. After a couple of days of mulling them over, I decided to plunk down the dough for a new iBike. I was convinced by a comparison between data from the iBike and the Quarq that the iBike is accurate enough for me, and costs a lot less than the other options.

The order handling was top notch. I ordered online from the iBike store, and received the unit a couple of days later in the mail. It was $800 and change. For that you get the iBike computer, a wireless stem mount, a cadence and speed pickup, and a heart rate belt. The hardware to mount the computer is included: zip ties, double sticky, and a couple magnets. The iBike Windows and Mac software is also included. There is a CD that has a trial version of TrainingPeaks in the package. Batteries for all the devices were included. The design thoughtfully uses one readily available battery type. Also there's a USB to serial dongle for the iBike/PC interface.

One minor gripe: No extra zip ties were included. It's pretty easy to screw up the installation of a bike computer and its sensors, so several extras should be included. One other minor gripe, I wish they'd implement the USB/PC interface as a USB mass storage device instead of the serial port converter. Then you'd be able to use it without a custom dongle and without installing drivers.

Since the iBike sensors are wireless, installation was very easy. The design of the mounts is clever and seem like they would attach easily to any fork and to any frame (for the cadence mount). The sensors are sensitive and pickup the magnet from more than a few millimeters away.

The stem mount for the bike computer was also easy to install. I managed to attach it upside down the first time, so I popped it off, scraped off the double sticky, and put it back on the right way in a few minutes. The mount was secure and stable as soon as I tightened the screws. The handlebar mount for the old iBike required a lot more fuss.

The instructions for installations were well written and clear. My only complaint is they should consider consolidating the collection of separate PDF instruction files into a single file. It's a little confusing to have multiple manuals, but really not a big deal. Some readers might prefer the multiple files.

The calibration of the iBike is a multi-step process. Since I've been using one for several years, I'm pretty familiar with the concepts, so it went pretty smoothly. You enter the combined weight of the rider and the bike (and all the stuff that you carry). Then, you calibrate the tilt sensor. Then you do a "coast down" and (new with the iBike Gen III) do a calibration ride. I performed the coast down and calibration ride three times over three days. The first two days, the wind was really strong and gusty, so I was in doubt about the results. The third day, the results converged and were reproducible.

I think the coast down and the calibration ride must be a little intimidating for a new iBike owner. If you buy a new iBike spend some time reading the manual and watching the videos. It will probably take you several tries to get it right.

Once I started to collect data I was pretty stoked at the new iBike application. It provides a clear view of the oodles of information the iBike collects: speed, power, elevation, and hill slope. It also automatically downloads weather data and associates that with your ride! You can edit files: join files, split files, and do all sorts of analysis of the data. You can zoom in on sections of data, like a hill climb. I've yet to scratch the surface of all the things it can do. The application provides a nice summary of the analysis in a text box so you can cut and paste (Rogers Road Hill Climb from Sunday Club Ride):

---------Selection Stats---------

Dist:        0.35 mi (0:02:59)

Energy:      59.9 kJ

Cals Burn:   57.3 kcal

Climbing:     163 ft

Braking:      1.2 kJ (2.0%)

          Min   Avg    Max

Power     184  334.6   526  W

Aero        0    3.2    16  W

Rolling    18   25.3    44  W

Gravity    58  297.8   485  W

Speed     5.0    7.1  12.4  mi/h

Wind      0.0    4.1  10.4  mi/h

Elev      455    544   620  ft

Slope     1.1   8.55  17.5  %

Caden      44   62.2   108  rpm

Aero: 0.229; Fric: 2.48

CdA: 0.353 m^2

Crr: 0.0072

248 lbs; 5/17/2009 2:49 PM

68 degF; 1013 mbar

So far the measured power lines up with past experience. I'll get more real data at the Leroy TT this week. I'm happy with the iBike Aero, I'll post a complete review in a couple of months.