What if it was possible to bust out a moto right behind the house? Not down on the lower 40 acres, but in the backyard with neighbors on all sides. For most motocross riders this is a far-fetched dream. Noise is the biggest issue with bikes in an urban area, but an electric dirt bike like the 2011 Zero MX makes the impossible a reality. Zero Motorcycles has been producing silent, eco-friendly two-wheelers for dirt and street in its Santa Cruz, California headquarters since 2006. For 2011, engineers went from top to bottom on the entire line, including the MX, to standardize and improve the effectiveness of this emerging motorcycle technology.
Zero is expanding its California-based design and manufacturing with a new facility in nearby Scotts Valley. This is just the beginning of a major overhaul that aims to establish Zero as a global brand rather than a liberal California start-up. A new wave of experienced motorcycle industry executives have joined the e-team and are combining their extensive knowledge of the two-wheeled world with the techno minds of Silicon Valley. For as much as Americans love to hate loud, obnoxious motorcycles, the European market has potential to be an equal or better fit.
Zero is cranking out five different bikes for the new model year including the Zero S street bike, Zero DS dual sport, Zero X off-road trail bike and the all-new Zero XU for urban commuters. These are in addition to the MX which is the stiffest and most aggressive EV in Zero’s lineup. A claimed curb weight of 196 pounds has this machine flying through the air and whipping around corners. Like the X and XU models, the MX uses a new Z-Force air induction system power pack that is rated for a maximum 2.0 kWH from the lithium-ion battery. These Z-Force batteries have a quick-charge option that cuts recharge time to around half, which means the MX can be back on the track in just over an hour.
Top Row: A new 71-tooth rear sprocket can be changed for altered performance. The lithium ion battery is now quick-charge and quick-change capable. The 2011 Zero MX looks cleaner and more refined. Bottom Row: The MX uses a more powerful Agni motor. The frame is powder-coated aluminum. HP Performance brakes have standard-sized pad mounts to allow for aftermarket upgrades.
According to Zero, one of its electric motorcycle takes roughly 500 parts to build, and of those 400 are re-engineered for 2011. Zero went through it machines and focused efforts on updating each model to share as many components as possible. Items like wheels, brakes, electrical connectors and switchgear are now standardized which helps Zero control costs and pass that along to the consumer. As part of the corporate strategy, Zero is placing more emphasis on the European markets where it expects to divert half of its production.
Glancing around the MX, the overall feel of the machine is much refined. The front end has been cleaned up with the speed sensor now attached to the motor shaft. Updated graphics give the bike a fresh look in its red/white color scheme and Bridgestone motocross tires (19-inch front, 16-inch rear) add seriousness. The motocross bike is based off the X model platform so it uses the same frame and most components. Suspension is different with a remote reservoir feeding the rear shock via a steel-braided line. Internal settings on the shock and fork are stiffer than the trail machine and it provides a noticeably harsher ride from its 8.7-inches of travel out back and 9.4 inches in the front. The suspension acts well on jump faces and landings, but the shock skips a lot over acceleration chop. The biggest jump on the track was just a hair out of our range, but we didn’t quite have the confidence to seat bounce it because the shock is a little springy. More time on the bike and some adjustment of the rebound likely would have helped.
Handling on the MX is light thanks to a skinnier profile than other Zero motorcycles and only 196 pounds.
Turn the key, flick the throttle switch and an Agni motor turns the rear wheel via a 420 chain drive and 13/71 sprocket combo (all Zero machines use the 13-tooth countershaft sprocket). One of the common topics with electric motorcycles is that the motor immediately produces maximum power. Cracking the throttle on the MX does not have the same effect as holding a gasoline engine full throttle and dumping the clutch. Power spools up slowly in the initial seconds before the battery-powered drive system puts down a slight surge of forward momentum. Acceleration isn’t strong enough to pull a wheelie without a little bump and some muscle. Riding the MX at a fast pace requires excellent cornering speed and flowing lines around the entire track – similar to riding gas-powered pit bikes.
The 2011 Zero motorcycles have dual power modes: economic and full-tilt. Running the bike in the power conservation setting is pointless during off-road riding for all but the most inexperienced and timid rookies. Entry-level riders can easily manage this machine with its light weight and optional meek power setting. Experienced riders will have fun as well, but are more irritated by the noticeable lag on throttle application. The biggest concern, however, is how quickly the battery drains. We tested quick-charge batteries that were on a constant rotation from track to charger, and had an equally frantic shuffle of heavy-handed journalists. It was difficult to tell whether the batteries were truly at 100%, but none of them lasted very long. Zero says it’ll run 30-60 minutes on a MX track. We say “BS.” Our estimate is 20-25 minutes at best, probably more like 15-20. We saw one journalist with a battery fresh off the plug run dry in roughly 12 minutes.
All the switching around proved that the quick-change feature is very effective. One bolt holds on a retaining bar which clamps the battery into place. It has a knurled top and can be tightened or loosened by hand. Remove the bolt and bar, pop off one plastic lead connector and the battery slides out. A complete swap takes about 20 seconds – very cool.
Braking is handled by a dual-piston hydraulic front caliper with 220mm wave-style disc. The rear disc is the same size with a single-piston caliper. There’s enough force from the HB Performance front unit to handle such a light bike, but it has very little feel at the lever. Stopping power from the rear is also acceptable, but the pedal has a sharp, blocky edge on the bottom which caught our boot a few times.
With more emphasis on the European market, Zero now offers all of its machines with street-legal kits.
Ergonomically it is a thin and nimble machine with a 34.3-inch seat height (optional low seat drops two inches). The riding position and rigid seat take a few minutes to get accustomed to, but the high handlebars help while standing. They do, however, have a lot of sweep. Footpegs are wide with fairly flat teeth. It does use a standard clevis pin now which allows owners to install aftermarket pegs. Rake is 26.4 degrees and trail is 3.5 inches.
The MX is eligible for a 10% federal tax credit, but to qualify it must be purchased with an extra battery. The additional Z-Force battery, sold with charger, costs almost $3000. Obviously that negates the entire point of a credit, but considering the quick drainage, it’s likely that someone who really wants to use their Zero a significant amount will need a backup anyway, so the cost savings is significant. The estimated expense of operating the electric MX is 21 cents per recharge.
The street-legal version includes lights, mirrors, higher gearing, sidestand and legal tires which make it nine pounds heavier (205 lbs) and $500 more ($9995). With a claimed street range of 25 miles, it isn’t a dual sport. That’s why Zero makes the DS model with a larger lithium ion, but it could serve as a quick errand runner and Zero says it will hit 57 miles per hour. The ability to run the MX on pavement is touted as an extra appeal for European buyers.
After riding the 2011 Zero MX, it’s obvious that this motorcycle isn’t going to serve as a straight-up replacement for any hard-core dirt biker. It lacks the true feel of a snappy motocross bike but provides a ride that is fun while it lasts. Fortunately, the performance threshold of electric motorcycles is perpetually expanding. New battery technologies and increasing development from component manufacturers will make the Zero lighter, faster and more durable in the coming years. Zero is quick to point out that the target consumer isn’t necessarily the guy with fire-breathing bikes already in his garage. Electric motorcycles are a market that is ripe for attracting new customers to the two-wheeled realm. Technophiles, city-caged racers and carbon-footprint tightwads have more reason than ever to join the two-wheeled ranks.