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tion information is to ride the bike in a circle for a few miles and then
hook it up to a digital multimeter. Czysz makes the best of it while
climbing onto the bike. In full leathers, highly styled hair, and designer
sunglasses, he looks like the Derek Zoolander of electric-vehicle rac-
ing. He even speaks with Zoolanderian opacity: "Other teams have
data acquisition," he boasts. "We have rider acquisition."
Adrian Hawkins, the lead MotoCzysz engineer, sheepishly holds
up his stopwatch and ledger. "Our acquisition system," he says.
Just before launch, the owner of the track---a practical joker---sug-
gests to Czysz that Imperial miles and U.S. miles are di erent.
Czysz turns to Hawkins, and asks how long each lap is.
"One point five miles," answers Hawkins.
"U.K. miles or U.S. miles?" Czysz quizzes.
Hawkins is stumped: U.K. miles or U.S. miles?
"U.K. miles or U.S. miles!" Czysz demands, more forcefully this
time. Czysz has a reputation as a screamer, and his voice is rising.
"U.S. miles," Hawkins stammers, gently telling Czysz that miles
are consistent across borders.
A voice from the small crowd that's gathered to watch comes
to Hawkins's rescue, politely informing Czysz there's an Impe-
rial gallon and a U.S. gallon, and perhaps that is the source of his
"It's gallons that are di erent?" says Czysz to no one in particular,
"Okay, I didn't know." And with that, he zips o .
THE BREAKDOWN LANE
Mission has even bigger problems. Like MotoCzysz, its bike com-
pleted one of the qualifying laps and broke down in the other---but
the team has no idea why. It's the night before the big race, the
one that counts; the bike is busted, and all Mission really knows
is what its rider Tom Montano can describe. The bike was feel-
ing really good---fast, even, he says. He was passing other riders
left and right, and then the machine just gave out. "All I can com-
pare it to," Montano says, "is when a gas bike starts lugging and
then binds up."
Hearing this, Jon Wagner, Mission's CTO, gets on his hands
and knees and opens the bike's power plant. It sits low in the bike's
frame just forward of the swing arm. "I'm getting a sinking feel-
ing that we've got a jenky motor," Wagner says. Placing the two
probes of a digital multimeter to the motor's guts, he takes three
measurements of internal resistance: .018 ohms for the first and
.021 ohms for the second two. The measurements are consistent
with a short in one of the three windings. "We may have to take
this thing apart and relacquer the coils," he concludes.
Wagner has found the failure, but that doesn't explain why the
motor quit in the first place. Mission was counting on its cus-
tom software to give it an edge, but forget stunts like "Segway
mode"---the Mission bike didn't even have brains enough to shunt
current away from an overheating motor. Even worse, when data-
acquisition tech Ray Shan downloads the race log from the bike,
he finds that Mission would have been better o if it hadn't used a
race computer at all. "We completed 31 percent of the track before
we broke down," says Shan, in disbelief, "but we used 40 percent of
our total power." Even if the motor hadn't blown, the bike would
have run out of juice before the end of the qualifier.
It's Seth LaForge, Mission's lead software engineer, formerly
of Google, who starts to connect the dots. What if the software
loaded on the ride computer was not updated to account for the
larger sprocket that was swapped onto the back wheel before the
race? Then the bike would be running faster than its speedometer
would indicate---and this would explain why Montano reported
passing other riders left and right.
To test LaForge's hypothesis, Shan recalculates the bike's speed
by extrapolating from the tachometer data. Since electric bikes gen-
erally don't have gearboxes, the relationship between rotor speed
and actual speed is fixed. The revised speed calculations indicate
that the bike was topping 100 miles per hour for the first seven miles
of the course---an energy-guzzling pace, for sure. But why didn't the
bike just run out of charge before the finish, like the MotoCzysz
bike? Why did it break down instead? The answer comes when
Shan superimposes the corrected speed data onto a motor e -
ciency map. "One hundred miles per hour is right at the edge of the
chart," says LaForge, gasping a little when he sees the graph. The
bike was redlining the entire way, dumping energy in the form of
heat. A faulty setting in the motor control software was feeding the
motor too much electricity. The bike just cooked itself.
LaForge would be a hero, except it's his code that didn't account
for the larger gear in the first place. Garbage in, catastrophic motor
failure out. The team works all night to replace the motor.
"OVER THE MOON"
On Friday, race day, the spectators at the start/finish line are in a
jocular mood. They've come to the Isle of Man to see the afternoon's
Senior TT, the "real" race, in which the boys with the biggest balls
UNDERDOG Arvind Rabadia (above), of the came-from-nowhere Team
Agni, wears the Indian flag as a cape in the winner s circle. Agni s home-
brew bike (left) crushed the flashy, high-design, high-technology bikes of
the American teams with a keep-it-simple strategy.
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