If you like irony, get a load of this: The next big buzz in the motorcycle industry could come from something completely silent. That's right, the electric bike market is currently surging (no pun intended), and some pit pundits are claiming it's only a matter of time until we're all trading in our gas cans for power strips. But before this drastic changeover can occur, we need to ask ourselves the all-important question: As soon as our bikes' motors don't go "braaap" anymore, how in the heck will we describe to our riding buddies what our bikes are doing?If the electric bike market were a class at your local motocross race, Zero Motorcycles would be leading the first lap after getting a solid-though somewhat uncontested-holeshot. This Santa Cruz, California-based company has been toying around with electric motorcycles for a few years now, and its new Zero-X Electric Motorcycle represents the latest edition of a wild idea nurtured by Neal Saiki, Zero's inventor and founder. Some of you may remember our test of one of Neal's first models-dubbed the Electricross Drift-R-that ran in the July 2007 issue of Dirt Rider. That particular machine was an early generation electric bike, and while the Drift-R and the Zero-X share many of the same components, the latest version is far more advanced and able to meet the needs of the gas-powered moto and off-road crowds. Although you didn't read about it, we also had the chance to ride Neal's second-generation electric bike at the MiniMoto SX event (where, I might add, both DR Executive Editor Jesse Ziegler and myself beat motocross champ Sebastien Tortelli, who was kind enough to give us an itsy-bitsy head start). To date, each machine in the Zero lineup has been better than the last, and the '09 version of the silent little bike is the most capable electric bike that we've ridden.So, what's the scoop on the new Zero-X? Let's start with the aesthetics. This bike looks like it came from either (a) outer space or (b) Walmart. The overall design of the frame and plastic is completely revolutionary (which is a nice way of saying "weird"), and the layout of the electric motor itself is likewise innovative (yep, here it comes again: "weird"). However, it makes sense that this little bike doesn't fit the mold; after all, anything fueled by a proprietary lithium-ion power pack may as well look like it. The recently beefed-up, aircraft-grade aluminum frame and swingarm give the bike an appearance that is part mountain bike, part dirt bike and part "Jetsons," but without a doubt the biggest eye-catcher on this machine is the massive power module cradled dead center in the frame. Weighing in at 45 pounds and taking up most of the room in the motor area, this rechargeable battery is the spark that makes the whole bike come to life.Speaking of life, this bike lights up with quite possibly the most painless starting procedure we've ever seen: You turn the key to top dead center, flip the on/off switch to "on" and then wait about 0.562 seconds for the green light to come on. Just like that, the Zero-X is ready to roll! Caution must be heeded here, however, as one can easily forget that the machine is on and an innocent flick of the throttle can turn into an act of war in the pits. But assuming that you started off on the bike correctly and made your way out of the pits, the Zero-X greets you with a hard-hitting snap of instant power. The delivery on this machine is, as they say, like flipping a switch, and the abrupt hit is something that the seasoned dirt rider never really gets used to. Powerwise, the Zero-X's stock curve is smooth, steady and strong. How strong? Well, Zero claims 20 horsepower, and I was able to climb Glen Helen's famed Mount St. Helens-the massive hill that Bubba rockets up at the Outdoor Nationals-with little trouble. As with the previous Drift-R model, this bike's power makes it surprisingly fast, and those expecting the insouciant powerband of a golf cart are in for a real treat. There are two switches behind the handlebar-think of them as "high/low" and "hard hit/soft hit"-that you can play with to alter the Zero-X's power. The "hit" switch doesn't seem to make a massive difference aside from tempering the character of the bike a bit, but the "low" setting makes the overall speed of the electric motorcycle much mellower. You have to toggle the key to go from low to high, which is a good safety feature.Fact: You should not swing a leg over this motorcycle and expect to ride it like a real dirt bike. Go check out an opinion on the Zero-X from another magazine or a bigger rider (see below) and you'll likely read something about how it broke the bike because it is "flimsy." Sure, compared to a full-size 250 the Zero-X is fragile, but that's because you're contrasting it with a big bike. In relation to a mountain bike, though, this motorcycle is quite strong. You truly have to ride it like a bicycle, and that means no blatantly hard landings and no slamming into things; you have to use finesse to ride the bike. At 151 pounds, the Zero-X is about all that the mountain bike-style fork and shock combo can take, and the entire chassis takes on a nimble, flickable feel in the dirt. Although not as stable as some would like, the lightweight feel of the machine certainly is a benefit to the power-to-weight ratio, and though the Zero-X can't take super-hard hits or big drops, it is still capable for mild trail scenarios.One thing that we hadn't done previously on an electric bike was ride it on serious off-road terrain, and this was perhaps one of the biggest disappointments of the Zero-X. Yes, it does well on flowing, twisty and even hilly terrain. But ride the bike anywhere that traction is a factor and you're in for a frustrating ride. In rocks-and I'm talking big, loose and sharp EnduroCross-style rocks-the Zero-X is a letdown. Why? Think about it: An abrupt hit combined with little weight equals a wildly spinning rear tire that just can't hook up. The power of the Zero-X may be good, but in trail situations where you need to finesse the throttle (think "flywheel weight" and "clutch control") getting all that power to the ground just isn't an option. Unless you are planted square on the pegs with your rear end over the swingarm, that 17-inch rear tire will be spinning and hopping like an RC car with a stuck throttle on a frozen pond.