B C
D
E
Fig. B: The original, overbuilt battery tray for the engine
compartment. Fig. C: The stripped motorcycle frame.
Fig. D: The swing arm, with a clearance hole and
mounting bracket for the motor. Fig. E: The electric
an electric charger and controller, and a motor with
just 1 moving part, the hub. No oil is needed, and virtually no noise or heat is produced during operation.
Clearly, this is not your father’s motorcycle.
An unmodified Rebel has a small 12-volt battery
under the saddle that powers the lights, horn, and
starter. Our new electric drivetrain needs to operate
along with this original electrical system. One option
is to keep the systems separate, by simply adding
a small 12V battery dedicated to the lights and such.
This option simplifies the wiring, but also requires a
second battery charger and more daily maintenance
— a solution that I found inelegant.
Instead, we spliced a 48V-to-12V DC converter
into the main power system and pulled our 12
volts from there. This taxes the batteries slightly,
especially when the headlight is on, but everything
recharges from a single standard wall plug. Xaoui
figured out the wiring, which was way outside my
comfort zone, and it took a few rounds of trial and
error to get it right (Figure F).
Conclusion
The GomiCycle project was a challenge. It required
a lot of people, skills, and tools. The original plans
said that the bike would cost around $1,200, go
F
motor, bolted to the mounting bracket on the swing
arm. Fig. F: The GomiCycle’s wiring, on an earlier
version of the bike, with 80Ah batteries. We stuffed
the electrical components into a camping cooking pot.
WHAT IS GOMI?
Gomi is originally a Japanese word for dust or garbage,
but it’s now slang used to describe anything that
people discard or no longer value. The word was
introduced to English speakers by best-selling author
William Gibson, who uses it to describe a near-future
dystopia of our material culture gone haywire.
In my working, gomi is DI Y. Gomi is tech-positive.
Gomi breaks the rules, but is responsible. Gomi is an
aesthetic choice — the best defense against mindless
materialism.
—Marque Cornblatt
60mph, and have a 40-mile range, but ours cost
almost $3,000, tops out at 40mph, and has a range
of 15– 20 miles. But the story is far from negative.
The GomiCycle is a great short-hop urban commuter bike with lots of torque and pep — it climbs
San Francisco hills without difficulty, and people
love it wherever it goes. It costs pennies per mile to
ride, and its lack of emissions makes the wind smell
that much sweeter.
Marque Cornblatt is a conceptual artist, roboticist, and
maker. He is the creator and host of Gomi Style, a DIY
lifestyle and design video series ( gomistyle.com).
Make: 155
