Electric drive overview and review article

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richard schumacher

Product overview (from one vendor, but usefully agnostic):
Technical note:

From the New York Times

Taking Hills in a Single Glide

HOT WHEELS Scott McKenzie of Newport Beach, Calif., on his electric
bike, whose range is 18 to 20 miles.
Jamie Rector for The New York Times


Published: December 31, 2004

"YOU just turn the key," said Kevin Penrose, pointing to the L.E.D.
controls on a flat-black, well-wired mountain bike outside Electric
Cyclery, his tiny, nondescript shop on the Pacific Coast Highway in
Laguna Beach, Calif. "The thumb lever is the throttle, and this button
is for turbo mode. If you go downhill, the blue light will show when the
regenerative charging kicks in."

These days, a visit to Costco, Wal-Mart, a local auto-parts store or
even eBay will present you with what may seem a baffling array of
two-wheel electric vehicles that promise to make commuting a breeze, or
serve as the best toy a kid ever had. Aside from having two wheels, the
common thread among these personal electric vehicles, or P.E.V.'s, is a
24- or 36-volt lead-acid or nickel metal hydride battery, a 250- to
1,500-watt electric motor and the ability to go as fast as 40 miles per
hour and as far as 40 miles on a single charge.

Sales of P.E.V.'s, have increased anywhere from 40 to 200 percent
annually over the last three or four years in the United States, said
Seth Leitman, an alternative transportation consultant for New York
State and, more recently, a P.E.V. retailer. And even though much of the
market is made up of inexpensive imports that can be unreliable (in
September, Target stores announced the recall of nearly 75,000 of its
$200 Chinese-made Red Dragon and E-Scooters), a significant portion of
it is composed of more expensive, powerful machines that offer the
range, sturdiness and reliability to serve as genuine transportation
aids. Mr. Penrose said that at his store he was having no trouble
finding customers for his two-wheel stand-up electric scooters, larger,
sit-down electric motorcycles and the wired-up mountain bike he was
showing, the WaveCrest Tidal Force.

With the exception of its wires and a pair of foot-diameter black disks
at the center of each wheel, the Tidal Force is a high-end,
front-suspension mountain bike whose folding frame was designed for
military use. The front disk holds a 36-volt nickel metal hydride
battery, and the rear contains a 750-watt direct-drive motor that runs
at 89 percent efficiency.

On a recent test run, the bike almost silently shot up the steep
incline of a street near the store with no pedaling whatsoever. Shifted
into pedaling gear as it reached the crest of a hill and started on the
downgrade, the bike hit around 30 miles an hour. Without pedaling, it
easily held 20. Then, on a steeply inclined fire road, the sensation of
quietly flying up an unpaved mile-long hill that normally requires a
granny gear was amazing. The bike's solid feel on the way down was just
as impressive.

At $1,500 to $3,000, a WaveCrest can be an expensive option for those
looking for an electric bike. There are many other options, ranging from
other electric bicycles to stand-up scooters to Vespa-style
e-motorbikes. Miles per charge and power to the ground vary greatly, but
a good bike or scooter should take you at least 10 miles on a charge. It
should also be able to recharge in three to six hours.

One of the country's largest P.E.V. dealerships is NYCE Wheels in
Manhattan. The manager, Mike Dolan, said that business at the store,
which sells and services higher-end P.E.V.'s, is growing. "More people
want these," he said. "Gas prices are going through the roof and taxis
are more expensive. Once people realize that they can get anywhere in
the city on their own terms, it becomes a really attractive option."

Mr. Dolan said that he had just sold a WaveCrest 750 mountain bike to a
trail rider from New Jersey and a Goped ESR 750 stand-up scooter to a
city messenger. Both these American-made products and the Taiwanese-made
eGo electric motorbike are among Mr. Dolan's best-sellers.

Although local laws vary, there are generally three legal
classifications for P.E.V.'s. The simplest two-wheel P.E.V.'s are small
stand-up scooters that occasionally offer seats. In most parts of the
country, these machines may be ridden on public roads where the speed
limit does not exceed 25 m.p.h., so long as their own speed cannot
exceed 20 m.p.h.

IN New York City, these scooters were nearly outlawed after a rash of
miniature "pocket rocket" motorcycle accidents led to an ordinance that
outlawed all gas-powered scooters and mini-motorcycles. In a last-minute
appeal, electric scooter riders were able to persuade the city to make
an exception for riding on public streets so long as speeds were
electronically limited to 15 m.p.h. They may not be used on sidewalks.

Depending on the jurisdiction, riders of electric bicycles are
generally able to avoid any legal restrictions if their bikes do not
exceed 20 or 30 m.p.h., and larger, Vespa-size electric motorbikes must
generally be lighted, blinkered, insured and licensed just like their
gasoline-powered counterparts.

The Web site visforvoltage.com, perhaps the best clearinghouse for
information on P.E.V.'s, and a few calls to Mr. Penrose's customers
suggested that range and power are the keys to happy cruising.

For Julie London, 43, of San Juan Capistrano, Calif., a WaveCrest has
meant freedom from the ravages of early-onset Parkinson's disease.
Formerly an avid cyclist and racer, Ms. London was forced off her bike a
few years ago by fatigue from Parkinson's. "I was absolutely amazed when
I rode one," she said. "I was literally overcome with emotion because it
was like getting my life back again. I was laughing uncontrollably for,
like, 15 minutes. Now I ride mine pretty much every day. It'll go 20
miles per hour, and if I'm too tired to pedal, I don't have to. It's
actually easier for me to ride than driving my car."

Ken Trough, a Web developer from Bellingham, Wash., was so taken with
P.E.V. technology that he created the visforvoltage Web site. Mr. Trough
makes a five-mile daily trip to work aboard a powerful Badsey Hotscoot
stand-up scooter. "I like personal electric vehicles because they don't
directly challenge the automotive manufacturing base," he said. "It's
very subversive technology. It gets people thinking about electric
vehicles. Once people find out what a good product this is, what it can
mean in their lives, in their living spaces and what it can do for their
transportation budgets and quality of life, I think it's a no-brainer.
You get more smiles per mile."
On Thu, 06 Jan 2005 10:14:37 -0600, richard schumacher
<[email protected]> wrote:

>Product overview (from one vendor, but usefully agnostic):
>Technical note:

[snip NYT article]

Dear Richard,

These sound like electric scooters with pedals added for

The .pdf's talk about 3-6 hour charging times, presumably
from 120 volt house outlets.

This suggests that the "regenerative charging" is window
dressing and wishful thinking.

They claim a range of around 20 miles at around 20 mph on
flat ground, using about 34 watts/mile. Elsewhere, they
indicate "500 watts" to travel at 20 mph on flat ground as
basic performance, with "3500 watts" for a 10% grade.

Whatever these figures mean, it sounds as if the rider would
exhaust the battery in one hour of output at 20 mph on flat
ground and need to recharge it from a house outlet for 3-6
hours. Without a house outlet, it doesn't sound as if the
"regenerative charging" has much practical effect.

Interestingly, motorcycle regulations apply on these in most
states if you go over 25 mph--meaning lights, license
plates, and taxes, though I suspect that many riders would
hope to ignore the law.

Carl Fogel