As I have mentioned before, my whole view of personal mobility was turned upside down the day I got a ride in a Tesla Roadster years back. Since then, it has been a goal to get behind the wheel of my own Tesla one day. To get closer to realizing that dream, I tried my luck in the e-bike business and co-founded the company E-wheels. However, since I don’t have a clue about running a business, I eventually left the company in the capable hands of my colleges, taking a few of those funky e-bikes I built with me.
E-bikes are for old people!
Utter nonsense! Well, I didn’t know that at first, but I was stubborn enough to give it try, and every single day for a whole year I did my daily 38 mile commute on my old bike retrofitted with a small 250 W front wheel motor and a 216 Wh Li-Polymer battery. During that first year of 6,200 miles I had replaced the motor (internal gears broke after 500 miles), the battery (cracked after falling on icy roads), the wheels (spokes wore out), the frame (made a new one with front suspension), and almost everything else. So, now I knew what I was dealing with.
Granted, e-bikes are for old people too! But the truth is, this is just another option of personal mobility for anybody who wants to save money. The extreme energy efficiency of e-bikes is what caught my full attention. An e-bike uses less energy per person-mile than anything else I can think of — including ordinary bikes, if you think in terms of energy converted to propulsion regardless of energy source (the human body is about as efficient as an internal combustion engine).
You get fit too, because you work together with the electric motor (at least on road-legal setups), but still I hear all this bickering about e-bikes being cheating compared to normal bikes. Cheating who? There is no way I would be able to ride those 38 miles every day on an ordinary bike, and that would mean using a car instead. Driving cars is cheating!
E-bikes are great!
So, I was hooked on the concept, and 7 years in, I have tens of thousands of miles in the saddle of different e-bikes, but it turns out I have never owned a factory built model. I have always built them myself, to suit my needs. Let me show you.
3 out of 9 ain’t bad
I am a bit low on bikes these days. The wife seems to think 12 bikes is too many for a family of 4, so I sold a few, and last I counted there were 9 bikes in my garage, 3 of them electric. And since I recently turned in my leased BMW i3, and winter is slowly releasing its grip, my long-distance e-bikes got a check up.
The roomy workhorse
My first tool at E-wheels was this bike of the long-john type. I used it for commuting to the shop and going out retrofitting and repairing motors and batteries on customers bikes. It was a show bike too, and it is of course fitted with fully functional solar power supply system.
I had seen the bike in Copenhagen, and found out it was a Danish design by famed Larry vs Harry. I got the bike as a DIY-kit and the very first BionX system that we had bought as a demo was fitted on the bike. It was an early release version in white finish, so it looked great on the Bullitt Milk model from Larry vs Harry.
I designed the box on the bike myself, so that a solar panel I had found on eBay would fit nicely. A few other components were fitted and the bike was now virtually able to charge itself while cruising along. Well, not really, because the panel is 50 W and the since the motor will use 250 W at easy cruise speed, a 1 hour ride would require a 5 hour charge. However, it is great to have a backup battery in the cargo box charging away on sunlight while cruising. On a sunny day, with an extra battery, I can go 60 miles non-stop before I need to charge, fully loaded with cargo.
This bike brings out a lot of smiles and fun comments. The strangest was a kid screaming: “Look, a remote-controlled bike!” On my daily route I ride by a local TV station, and eventually they could not resist their curiosity and had to invite me in to do an interview.
Later I plan to upgrade the bike with the BionX D-series motor. It will make so much more sense on a heavy bike like this. The higher continuous torque capacity on the D-series (25 Nm) will prevent thermal cut off when this thing is loaded with kids and cargo. Our local delivery service Velopak chose the D-series for this reason.
Why not a 3-wheeled cargo bike? Well, while it would be more practical and roomy, the specialty of the Bullitt is the quality of the ride itself. The bike is very stable at high speeds, it has very good balance, it has very good hydraulic disc brakes, and it is just so much fun to ride. You can even get a steering damper if you ride stupid fast! Check out this hilarious New York Bullitt cargo bike race.
Frame: Larry vs Harry aluminium Bullitt Milk
Motor: BionX SL 250 W HT direct drive 3-phase brushless DC, 9/40 Nm (continuous/peak)
Battery: BionX XL 48V Li-Ion 423 Wh (18650 cells)
Charger: 24V 90 W (charge time 5 hours)
Lights: Supernova 3.5 W LED connected to BionX battery DC 6V output (Console control on/off)
Extras: 50 W solar panel with charger, 12V Lead Acid and 12V DC/240V AC converter (max 300 W output that I have used for charging, music, beer-cooling and work lights).
Weight: approx 40 kg
Total cost: approx $5,000.
The laid back speedster
This is another one-of-a-kind e-bike creation. I wanted to try the comfort of a recumbent bike, but was not into laying flat on my back with pedals in the sky, so I engaged a couple of friends, and after a few sketches we came up with this long wheel base thing.
The frame is two standard bike frames chopped up and welded back into one. The rear wheel is 26 inch, and the front wheel is 20 inch, just like the Bullitt. It’s a great ride. However, it is only suitable if you have a death wish. The rear brake is useless. The weight on the front wheel is not enough to get any grip, and the motor is a devil.
3 chains are joined together to reach from front to rear and the many gears are redundant due to the massive direct drive motor from Falco eMotors. 750 W (2000 W peak) with a peak torque of 60 Nm. It’s throttle operated, so you can just relax and enjoy the ride at 30 mph and pray you don’t hit anything.
The naked battery is a massive pack of stacked polymer cells and it was bloody expensive. I built it into a sturdy box with lot of foam damping. The main on/off switch can handle 120 Amps, and inside I put 2 40 Amp fuses. The motor can handle 40 Amps at 54V peak (battery fully charged is 54V, empty is 44V). The range is easily 60 miles at top speed, due to the low riding position and low wind resistance.
Obviously what needs to be done here is to mount proper disc brakes, and the frame needs reinforcement because it simply flexes too much at high speeds. Scary! I mostly use the bike for show, but I must admit I occasionally take it to work on warm days. It is so comfortable and I just love it to bits.
Frame: 2 standard steel bike frames welded into one long wheel base
Motor: Falco eMotors 750 W Hx 3.0 direct drive 5-phase brushless DC, 60 Nm (peak)
Battery: Falco 48V Li-Ion-Polymer 1000 Wh
Charger: 48V 100 W (charge time 10 hours)
Weight: approx 30 kg
Total cost: approx $3,000 (Battery is half of that!)
The exotic beauty
How do you choose a favorite? I just can’t. I have realized that I just need a bike for every purpose, and this bike has a very special purpose: powerful and silent simplicity. I planned this bike for a full year. The base was the frame, which is bamboo.
Early on, I lured my partners in the before mentioned e-bike business into trying to sell bamboo-bikes. Turns out nobody wants bamboo bikes. We had a dozen in stock, and we sold only a couple. It’s a shame, because bamboo does the job in a very unique and exotic way. So when I left the company, I took a couple of frames with me.
Bamboo is very strong. Bamboo is flexible. Bamboo is beautiful. The company Zambikes in Zambia is known locally for their ambulance bikes (yes!) and internationally for their bamboo frames. They are not cheap, but I have not regretted this bet. It is very hard to describe how a bamboo frame feels. It sucks up all minor vibrations, and it becomes very evident on gravel roads. No rattling sounds. Just silence. The frame flexes just enough to manage longitudinal surface grooves like an off-road motorcycle does, making the ride effortless, even without front suspension.
The motor is very powerful, but for the time being is limited to 20 mph, because I use this bike a lot, and I am not interested in getting on the wrong side of the law. If the proposed law of a more liberal use speed-pedelecs goes through, it is a very simple operation to reprogram the system for a higher top speed.
Every single component on this bike is carefully chosen. Nothing is overdone. Everything is just right. One important point about this bike is that it had to be extremely low maintance. That’s why things like single speed gearing, a stiff front fork, and cable disc brakes are used. No extra gears are needed when you have 50 Nm peak at your disposal. The Avid BB7 brakes are the best in its class, and they are unbelievably effective.
One thing that actually may be a bit overdone is the front light. The top of the line Supernova M99 Pure is so powerful that I choose the legal road version. It has automatic switch between daylight and night mode. It lights up the road like the headlights of a car!
Frame: Zambikes bamboo MTB joins of hemp
Motor: BionX D-series 250 W direct drive 3-phase brushless DC, 25/50 Nm (nominal/peak)
Battery: BionX D 48V Li-Ion 555 Wh (18650 cells)
Charger: 48V 90 W (charge time 6 hours)
Weight: 20 kg
Total cost: approx $7,000.
E-bikes are for everyone!
So there you have it. I think e-bikes gives you a lot of benefits, and as I have shown you here, you are not limited to what you can buy at the stores. There are lots of different retrofit systems out there, so if you are not afraid of a bit of simple mechanics, you can build whatever kind of bike you need.
Over the years I have enjoyed these bikes for business, commute, and fun:
Disclaimer: I have no financial involvement in any companies mentioned in the text of this article or in the video footage.
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