“On June 4, 1896 in a tiny workshop behind his home on 58 Bagley Street, [Henry] Ford put the finishing touches on his pure ethanol-powered motor car. After more than two years of experimentation, Ford, at the age of 32, had completed his first experimental automobile…The two cylinder engine could produce 4 horsepower…achieving a top speed of 20 mph (32 km/h). Ford would later go on to found the Ford Motor Company and become one of the world’s richest men.” —Wikipedia
I’m gradually reducing my car dependance. I enjoy traveling to meetings, hauling groceries, and taking my kids to their dental appointments all on my bike. But one of the few remaining compelling reasons for using my car is to carry adult passengers. For a variety of reasons my adult friends and family do not feel comfortable hopping onto my longtail cargo bike. Can bicycles ever fulfill the role of carrying adult passengers? I believe they can, and (like Henry Ford) I’ve built an experimental vehicle to test my conviction.
Here are the design goals I began with: build a bike that can safely and comfortably carry both a 200-pound driver and a 200-pound passenger at an average speed of Continue reading →
No Virtue Required: Car-Lite Family Transportation Is Less Expensive, Faster, and More Flexible than Car-Encumbered Transportation
In his recent post, my co-blogger Don writes about “the virtue in choosing the right [transportation] tool for the job”. I realized that my own family makes regular use of five, count ‘em FIVE transportation options: walking; bicycling; busing; driving various CarShare and rental vehicles; and (in dwindling amounts) driving my wife’s tiny red Mini. Yesterday epitomized our highly flexible family transportation: we criss-crossed Ithaca together and separately and then at the end of the day we all landed together on our couch like the opening sequence of a Simpson’s episode.
Here’s a little photo essay about my family’s bicycles. I’m proud to say that we use our bikes a lot. Each bike is tailored to its user: I drive a cargo bike capable of carrying passengers and cargo long distances; my wife drives a slower and lighter but more stylish bike; my 11-year-old daughter Thea and her friend JJ drive bikes tailored to their 2-mile drive to school. (My son Jasper, aged 15, resists having a bike. He pretty much walks wherever he needs to go.) Ithaca is hilly, so it’s important for a utility bike to have an electric motor. I’ve spent a lot of time over the last couple of years experimenting with electric bike motors and other accessories. Maybe you can benefit from my discoveries.
The Aqua-Xtracycle is a do-it-yourself amphibious electric cargo bike. This video shows how it works, and the photo gallery below shows a bit of our development process. In a future post I’ll describe how you can make your own Aqua-Xtracycle.
Caution: shop talk blog post intended for do-it-yourselfers. For my recent 240-mile journey I created what I call my “trip batteries”—batteries that I can attach to my bike to augment my regular batteries, but that I don’t intend to carry around on a daily basis. As such, the main design criteria for these batteries is that they be inexpensive. I don’t want to pay the big bucks for a battery that I only use once in a while. The obvious choice is SLA (sealed lead acid) batteries. These are the same kind of batteries used in cars, and the technology is almost 100 years old. E-bikers out there may poo-poo this choice of battery. After all, compared to my lithium batteries, my SLA batteries are heavy (20lbs vs. the lithium’s 15lbs), not quite as powerful (600wh vs. the lithium’s 720wh), don’t last as long (300 charge cycles vs. the lithium’s 1,500) and they are dumb (that is, they don’t have a battery management circuit board in them to prevent human error from damaging them, although most controllers provide the necessary protections). But they are cheap. I can put together a 10ah 36v battery for about $120 versus a 10ah 36v battery for $600.
Could this be our new logo? Have a better idea? Let us know.
I’m planning to start an electric bike club with some friends in Ithaca and we don’t yet have a name. Can you help us think of one? Finding a name is an important first step for any organization. It will force us to think about the goals of our group. This grueling process may release our hidden differences, but the fires of our disagreement will forge in us a new a sense of unity! Right. We invite you to participate.
Ithaca is especially suitable for ebikes. The largest part of our community is students. A very visible part of our community is environmentalists. Both of these groups would benefit from biking: students need an inexpensive mode of transportation and environmentalists want transportation that better fits with their values. But both groups are held back by (among other things) the incredibly hilly terrain here. An ebike erases that impediment. For a variety of reasons the bike stores here are unable to step up to the plate to promote ebikes. That’s where a club comes in. Our club is all ready to go except for one thing: we lack a name. Here’s some thoughts that may guide your club naming.
I recently received the following email from a reader:
I was researching cargo bikes and just kept seeing your blog pop up. I am very interested in doing a similar set up as yours. I also was interested in elMundo initially. A sidenote on the weight of the elMundo: they are now selling it with the electric components already attached and the shipping weight of the bike and box was 100 lbs. which seemed like a lot.
My question is pretty simple. I haven’t tested a Rans Hammer Truck in person since this is just the planning phase. I read the height of the bike had a 31- 38 inseam. I am 5’5″. I wondered about the comfort of the frame. And if your wife was shorter than you and found the Hammer Truck comfortable… ? Also just to pick your brain (and thank you very much in advance) how did you like the Hammer Truck handling without the electric assist? You mentioned you test rode it for a day…
My plans are just like yours, I want to use it to take my 2 kids to school and errands and fun – reduce car use in general. The kids are 6 and 4 and the bike trailer is just not cutting it these days.
Oh yeah! one more question. I read your post worrying about brakes. Currently with the bike trailer I often hop off and just walk up the hills. My question is, is a cargo bike easy to walk with when it’s carrying about 50- 60 lbs.? Or very tippy?
Thanks for the blog. I am surprised the Yuba people haven’t offered to let you test drive their bike. Surfing I ran across another cargo biker’s blog who actually bumped into the founder/owner while on a bike tour in Europe and had a very good impression of him and a good talk with him.
Thanks again. Happy biking! I am so happy I stumbled across your blog.
Thank you, Jessamin. Your email reminded me that there are still a few things I can say about the Hammer Truck. For many months, I have felt a bit uncomfortable about my bike’s relatively high cost, and I have been researching less expensive bikes that might appeal to a broader market. That has been an interesting project, and I intend to continue doing it for a while. But I don’t own these bikes or ride them on a daily basis. My real expertise is my particular bike, and answering your questions gives me an opportunity to return to familiar territory.
To answer your question about bike height, my wife rides the Hammer Truck very comfortably. At 5’4″, she is a little shorter than you. As you can see in this photo, the seat stem for the Hammer Truck is angled at approximately 45 degrees. When you lower the seat an inch, you also get an inch closer to the handle bars. This seems to scale well for most body types.
Hammer Truck seat stem
While you’re looking at the seat, I will also mention that the inclination of the seat is adjustable. When I first started riding the Hammer Truck, I had the seat almost parallel to the ground, like a normal bike. However, the Rans web site shows their seats tipped forward, so I tried it. It feels a bit like standing and leaning against a wall. Tipping the seat puts a little more weight on your feet, and that’s what you want when you’re riding. The slight curve of the seat back allows you to dig in for a little extra leverage when you need it. These are all helpful when you really need to crank!
The Hammer Truck worked fine without the motor. If we still lived in Denmark where it’s notoriously flat, I wouldn’t have needed the electric assistance. I’ve spent so much time on this blog bemoaning the hills in our neighborhood, I decided I really needed to show you what I mean. Yesterday afternoon, I put my 9-year old son behind the camera, and he took a video of me pushing my daughter up the hill, riding without assistance, and riding with the motor providing maximum assistance.
As you will see, this hill is a monster. When I write about heating issues with my motor and brakes, you need to understand that I’m pushing both to a limit that most people won’t encounter. Despite my occasional complaints, it’s pretty amazing that this bike can handle this kind of challenge. (Note: the scraping noises heard in the video aren’t the bike — my son was balancing the camera on a mailbox to keep it level, and scraping as he pivoted the camera.)
You can also see from the video, pushing the bike uphill is possible, but not fun. The side bars that carry loads so well are approximately where you want to put your feet, so you have to lean over a little. It might be hard to see in the video because I’m already leaning against the hill so much. It’s not as tippy as I thought as long as both hands are on the handlebar. It would be almost impossible to do one-handed.
You might notice my slightly hunched posture when I’m riding in this video. With the Hammer Truck, you generate power by pulling back on the handlebars, engaging the same muscles you would for rowing. In my case, I can produce more cranking force this way than I would standing on my pedals on a traditional bike. It’s more of a full-body workout, especially when I turn the motor off. However, this might not be a good idea for people with fragile knees.
Speaking of cargo bikes on hills, this is probably a good place to mention one of my favorite web pages: Cargo Weight Calculator. The calculator which gives you a rough idea about how much weight you can expect to haul up hills of varying steepness. Another page on the same site shows you how to measure the grade of a hill. Every time I turn off my motor and I’m reminded how hard it is to climb a hill with a load, I return to this web site, punch in the numbers, and I’m assured that there are real, mathematical reasons why it’s difficult. It’s not because my motor is making me lazy.
Sometimes I get distracted by all the details of this project: the specifications, the prices, the compromises. My blog is kind of heavy on that sort of thing. I occasionally need to remember that there is an emotional and even inspirational side to cargo biking, and my favorite blend of practicality and inspiration comes from the Couch Potato to Full-Time Cyclist blog. If you haven’t seen it, check it out — it’s really a great counterpoint to what you read here.
I was frustrated about having to repair a flat tire every hour or so and I was concerned that I might run out of patches. I needed to get to a bike shop soon. There was a Walmart 12 miles away in Rome. Could I make it? Long story short I made it. I bought three inner tubes, two patch kits, a floor pump, a tire, and a file in case I needed to convert my presta rim to schrader.
Any kook can slap a solar panel on a bicycle and call it a solar bike. How am I any different? Mainly in my lack of ambition. I don’t want to create a ground-breaking product that will rocket me into the halls of fame. I just want to charge my battery however much I can within my budget. I just want to do the experiment to find out if adding a solar panel to my bike is worth the effort and expense. And if it is, I want to post instructions on my blog here so others can follow in my footsteps.
People see my bike and they expect that the solar panels power the bike completely. The reality of course is that the solar panels are an accessory to an accessory. First of all the electric assist is an accessory to you the bicyclist who is pedaling. Secondly the solar panels are an accessory to the electric assist. The solar panels supplement the electric assist’s batteries in those few instances where you can’t get to a power outlet. So despite the panels’ physical prominence on my bike and in our imaginations, currently they have only a minor role in actually making the bike go forward. Not insignificant, but minor.
What would it take to give the panels a major role? At least a four-fold increase in power. Currently the panels produce about 25 Wh per hour. 100 Wh per hour would be very useful for a long trip since it takes me about an hour to use up 100 Wh. That means I could accumulate energy about as fast as I use it. I could go indefinitely (on a sunny day). I think it’s entirely possible to get a four-fold increase with existing technology. Just adding more panels is a start (perhaps as a canopy over the driver). And it may be possible to make the panels more efficient by adding a charge controller with sophisticated electronics (such as Power Point Tracking).
Bicyclists out there may be wondering “If the power you get from the solar panel is so small, why not just take all that crap off your bike and pedal the damn thing?” This is a very good question that has been nagging at me throughout the ordeals of this trip. I have to keep in mind that this is just a beginning. The point is not to just reach my destination here and now. The point is to pioneer a new type of vehicle. It’s not a solar car–it has pedals so that its human can supplement its power if necessary. Is it a bike? Whatever it is, it is a vehicle that is so lightweight, narrow and slow that even the meager power of the sun can power it.
Adirondack Gateway Campgrounds = heaven
catching photons in Hinckley State Forest
“Can the solar panel drive the electric motor directly?”
“Did you make it yourself?”
Allow me to explain. My vehicle of choice is a “stoked Xtracycle”. (For those of you not “in the know”, an Xtracycle is a type of cargo bike that has an extra long frame. And “stoked” means that my bike has a Stokemonkey electric motor that helps me out on the hills.) In general this summer I’ve been biking 10 to 20 miles a day and then recharging my battery overnight by simply plugging it into an outlet. However, next week I’m going on a 3-day 240-mile camping trip through the Adirondacks where I might not have access to an outlet. The solar panels will help extend the range of my bicycle. So to answer your questions:
“Why do you have solar panels on your bicycle?”
I use them to extend the range of my electric cargo bike for long trips (plus they were fun to make). I will carry two batteries on my trip, each giving my bike a range of 20 to 40 miles. On a sunny day the solar panels can recharge one of the batteries while I am riding, adding an additional 20 to 40 miles for a total range of 60 to 120 miles a day. I anticipate some hills and I’ll be carrying a load, so a 60-mile range is probably more accurate. I may need to pedal the last few miles on some days.
“What do you do when it’s cloudy or it rains?”
I plan to stay in a hotel some of the time and recharge my batteries there.
“Can the solar panel drive the electric motor directly?”
Not really. The solar panels don’t produce enough electricity instantaneously. For example the solar panels only produce about 40 watts of power at a given moment, whereas my bicycle needs about 400 watts of power to go up a hill. The main purpose of the solar panels is to charge the battery over time. Since charging happens slowly, 40 watts is enough to charge the battery. It takes roughly 10 hours of charging to store one to two hours’ worth of electrified riding time in the battery. And one to two hours of riding translates into 15 to 30 miles.
“Did you make it yourself?”
I already had the stoked Xtracycle, which is described on my About This Bike page. As you can read there, an electric cargo bike can be had for $1000 to $3500. And I had already constructed the canopy frame for a previous project, the Bike Wagon Canopy ($150). I found the canopy was somewhat wobbly with the weight of the solar panels so I had to strengthen it with guy wires. It remained for me to add the solar panels and the electronics. I used maritime-grade solar panels that were designed to keep sailboat starter batteries charged up, so they are extra-sturdy and consequently somewhat expensive. I’ve since seen panels with almost twice the power at 3/4 the price. Cost of panels: $900 to $1200. I am using three 12-volt panels in series to produce the 36 volts required by my battery. I spent a lot of time researching what sorts of electronics I would need between the panels and the battery, and finally concluded that I can just plug the panels into the battery directly. (I plan to write more about this in a later post.)
Total cost for a solar bicycle: $2050 to $4850. Not bad for a vehicle that can get you both out of the car and off the grid.