Short of bolting a sidecar to your bike, iBike’s Dash CC Deluxe cycling computer is as close as you can get to taking a personal navigator along for a ride.

Actually, its computing brains are supplied by your iPhone, which is sort of like a personal navigator anyway. So let’s just call the device a sidecar for your little Apple buddy.

The Dash CC Deluxe system has a few different components: a case that mounts on your bike, various sensors (also included) that attach to your bike and your body, and a free iPhone application that turns your iPhone into an incredibly detailed bike computer. It’s compatible with the iPhone 4, 3Gs/3G, and the iPod Touch generations 1, 2 and 3.

The case, called the Phone Booth, is sturdy enough. It bolts to your crossbars with some minor wrenching, and the case itself slides in and out securely. iBike may as well have allowed you to bolt the whole thing on, since the Phone Booth is too bulky to be used as a regular case off of the bike. There’s no way you’re getting that thing into your jeans. On the bike, though, it proved solid — it survived a few laydowns and is completely waterproof, which is great news if you get caught in a downpour.

When your phone is in the case, it’s able to communicate wirelessly with the included sensors. The list of ride data the Dash is able to collect is too long to run through in full, but among them are the basic cycling computer mainstays: cadence, heart rate (a strap/monitor combo is included), speed, distance traveled, and hours logged. But your iPhone is much more than a bike computer, so the Dash goes well beyond the basics.

Since your iPhone is rocking GPS, you can use the maps feature to track your location wherever you go. Forget about getting lost. You can map out your route and follow your charted course, keeping an eye on your progress, and even the weather, as you ride.

It’s also easy to stare at the thing for too long. I almost drifted into traffic on more than one occasion when mesmerized by the screen in front of me. Keep those eyes up, cowboy. However, that’s also one of the Dash’s stronger suits: your iPhone screen is huge compared to most bike computers, and that big color display makes glancing down at your current stats when you’re cranking on your bike a lot easier.

The GPS function drains your battery, though, so iBike did the smart thing and included a rechargeable lithium-ion battery to bolster your phone’s running time. During longer rides, the battery held out for two hours before going to the iPhone’s internal battery.

While you’re riding, your iPhone retains all of its functionality. You can listen to music, check your email, update your Facebook status, and make phone calls on a bluetooth headset. All at your own risk, of course.

Once you get home, you can e-mail the ride’s data to your computer, where you can track your stats — ride time, cadence, speed, heart rate, elevation, including averages and high points — using the matching desktop software. You can mail it to anyone else who has the free desktop app, like your coach or your training buddies.

Speaking of your buddies, you can also plug your data into Google Earth to revisit your ride and rub it in their faces. It was a blast to go back and retrace every switchback of a good, long mountain bike ride.

While the stat-tracking and trip data (and lap tracking, and cumulative readings) are meant to appeal to the harder-core cycling geeks, its weight might not — if you’ve just dropped a few grand on a Campagnolo Super Record groupset, the Dash’s 11 ounces (including the iPhone) might be a turn-off.

Since I’m not a gram-counter, I didn’t mind the weight. I did mind that I had to take my iPhone out of my everyday case and put it in the Phone Booth every time I wanted to use it. In a perfect world, the Dash’s Phone Booth would be small enough to take off the bike and put it in your pocket.

Also, it doesn’t have a power sensor, which is another potential turn-off for the hardcore athletes. But it does have the ability to connect to ANT+ DFPM power sensors like PowerTap hubs, as well as any other ANT+ sensor you may have strapped to your steed.

All different types of cyclists can appreciate the Dash’s wealth of data: messengers, mountain bikers, long-haul tourists. Even commuters — if you’re schlepping your iPhone to work anyway, it gives you something to geek out on once you get to the office.

WIRED Easy setup and use. Phone’s display is better than any dedicated computer. GPS keeps you from getting lost, Google Earth tracking lets you relive your two-wheeled glory. Dashboard is customizable. Piggyback battery is a nice addition.

TIRED Too heavy for the weight-conscious. Phone Booth is too bulky for off-bike use. $300 is a lot of cheese, but simpler/cheaper versions are available.

Photo by Jim Merithew