How to turn the Honda Cub into an electric motorcycle
With a population of 1.4 billion, China should be a goldmine for bike builders. But it’s not: motorcycles are banned in many of the biggest cities. In Shanghai you can still get a license plate for a bike, if you have 450,000 Renminbi (Yuan) to hand. Which is about US$67,500.
On the other hand, you can get a license for an electric bike for about 50 RMB, which is $7.50. China is tackling pollution by shifting the market towards electric motorcycles, and the small number of local custom builders are adapting fast.
Shanghai Customs is one of those builders. We’ve already shown their stylish electric street tracker, but shop boss Matthew Waddick reckons it’s this new eCub that will soon become his biggest ever seller.
“Shanghai is a pushbike city first and foremost,” says the expat New Zealander. “Always has been, and always will be. Even before millions of cars and scooters took over, everyone used to get around on bicycles. The city is flat and beautiful, and with the architecture, shops and crazy traffic it’s perfect for electric scooters.”
Most of the ebikes in Shanghai are cheap and nasty, and powered by inefficient old-style lead-acid batteries: China’s most ‘westernized’ city has not yet cottoned on to the idea of stylish, high quality electric scooters. But Matthew is determined to change that. “I noticed that the Cub frame is everywhere in China. I think it came ‘off patent’ years ago, and the Chinese swooped on it.”
“China is horrible for motorcycles, but with electric bikes we have an opening—and an amazing opportunity. Components for many of the world’s top brand electric motorcycles are made here.”
If you’re attracted to minimalism and timeless design, you probably appreciate the elegant simplicity of the Cub frame. Its size lends itself well to an electric scooter conversion.
“With the eCUB, we wanted to put down our own stamp of authority—and build a bike that was not only a piece of art, but could also be ridden. It needed enough range and speed to be used as a daily ride. The idea is to create an ‘eCUB culture’ in Shanghai.”
Matthew started by welding a cover over the part of the frame where the engine used to be. He’s also made mounts and fixtures to secure the stainless steel box that holds the battery pack and battery management system. But he’s left the holders for the rear foot pegs in place, because the eCub comes with a dual-seat option for riding pillion.
“I modified the swing arm to accept the electric motor, and then laced it onto an 18-inch gloss black aluminum rim,” he explains. The chunky-looking 3.25×18 tires are from one of the better Chinese tire brands, CST. The adjustable suspension, in brushed aluminum and black, was custom made by a suspension specialist 200 miles away in Zhe Jiang.
Control comes from a 3-wire motorcycle-style throttle: “It gives a nice snapping carburetor effect,” says Matthew. But the real achievement is hiding all the wiring that comes with a fully electric bike, not to mention the battery pack.
“With electrics there is always something to do. I’m working with a renowned electrical engineer, the Australian Sam Dekok, to reengineer some motors to improve performance. Then there’s the internal componentry in the controller, the different fast charging solutions, battery sensor technology … the list just goes on.”
The eCub has three types of regenerative braking: switch, throttle and variable. “I have wired it up to the switch on the left brake lever. Releasing the throttle also activates motor braking, which slows the bike like a traditional gas motor and puts volts back into the cells.”
Although the eCUB looks ultra minimalistic, it’s fully wired up with a front headlight, a rear brake LED and flashing LED blinkers. The 60v power system is stepped down to 12v to run the lights. “The Cub is not a big bike, so it is literally jam packed with wires.”
Power comes from Panasonic Sanyo Li-ion cells in a 1.2 kW pack, wired up to a 2000 W hub motor. Three heavy-duty phase wires head into the controller.
“There are wires everywhere: phase connections, throttle wire connections, hall sensor wires, switch wires, boost, reverse low speed, regen brake switches, 12 V systems, the key ignition and more. It’s really quite something—but also a super fun experience that just becomes addictive.”
Other than a tiny bit of grease on the steering head bearings and front drum brake, there are absolutely no fluids of any kind on this Cub.
So we know the engineering is good, and it certainly looks good, but how practical is the eCub? “I was a bit nervous, because you really never know until you try. I’m an 80 kilo (175 pound) male and we went out late one night and just kept riding, from full to empty. We hit our target 50:50 mark—a 50 km range driving at 50 kph.”
That’s a huge achievement given the compact size of the bike, and makes the eCub a practical vehicle for city use. “With the Kelly KLS controllers acceleration is smooth. The app also separates the speed ranges and torque, so at the touch of a button you can program your riding style. Personally I like the ‘high’ torque settings at the low end—for take off—with ‘cruise’ at the top end for battery conservation.”
There are still tweaks to be done. The motor is a little too big for the battery pack, so the controller limits the current to 35%.
“I have had the eCUB up to 80 kph and I’m sure it could do 100—but these li-ion batteries are not cheap, and the last thing I want to do is destroy them!” says Matthew. “It’s really a balancing act. But electric bikes are not replacing gas motorcycles for a while yet. They’re an addition, and good city commuters. A ‘turn the key on and go’ kind of thing.”
Much as we love the sound and smell of conventional bikes, it’s good to see custom builders testing the waters in this way—and the tide is undoubtedly going the way of electric at the moment.
“Until now, I’ve found the electric bike scene dominated by tech-orientated builders who put less emphasis on style,” says Matthew. “So it’s been really exciting speaking with top custom builders (many of whom have been featured on EXIF) and seen their interest in building electrics.”
“Hopefully more custom builders will get bitten by the bug, and develop a new custom electric scene.”
Electric power is already creeping into classic car world: how long is it going to be before the same happens to the custom moto world? We can’t wait to see what happens.