Today’s milestone was our first family trip to Lowe’s by bike. While I have no special love for this big box store, it’s sells some things we can’t find elsewhere in town. It’s also located on the farthest edge of Richmond, nestled next to a interstate exchange and the typical sprawl of chain businesses and parking lots that accompanies them.
None the less, we found routes there and back that involved minimal time of busy roads, arriving in 18 minutes*. In total, we rode about another 20 in-town miles today running typical errands. Again this seemed very reasonable on the electric cargo bike, and a workout on my fast recumbent to keep up. Continue reading →
[NOTE: I originally posted this article on June 15, 2010. In mid-August, Kona officially added the Electric Ute to its 2011 catalog (here). I've re-edited the article to incorporate new information and correct a few mistaken assumptions on my part. I compare the Ute to the latest version of the Yuba elMundo and the upcoming Trek Transport+ here.]
One of our local bike shops (Alki Bike and Board) received its first Kona Electric Ute on Saturday. The owner knew that I was keenly interested in taking this bike for a test drive, and he immediately notified me of its arrival. I got to the shop while they were putting the final touches on the bike assembly.
The Kona Electric Ute will have a chapter in the history of cargo biking, because it is one of the first cargo bikes from a well-known manufacturer that includes an electric motor as an integrated option. Most of the electric-assisted cargo bikes currently on the road are after-market builds, which makes them more complicated and expensive for the average consumer. With a retail price of $2599, the Ute is considerably less expensive than my Rans Hammer Truck / BionX motor combination. The question is, did Kona skimp on anything to hit that price target? Does it still feel like a quality ride? Could I use this bike to do the same chores I do on my bike?
First impressions
The Ute is a good-looking bike, with golden paint (but not too flashy) and a nice, thick wooden cargo deck mounted on top of the long, thin battery. It’s not an Xtracycle, and it hardly looks like a long-tail bike. It’s not just nicely-proportioned; the weight is well distributed between the front and rear (by contrast, my bike is quite tail-heavy if you try to pick it up). The Ute is also quite light for an electric cargo bike. Unfortunately, I didn’t have a scale to get an accurate measurement, but I estimate it weighs about 45 pounds.
Kona Electric Ute
Cargo deck
Despite the Ute’s pleasing proportions, the cargo deck is quite long. It provided ample room to seat both my children during our test ride. However, it’s several inches narrower than mine, and the kids complained that it wasn’t as comfortable to ride on.
The owner of the shop was surprised that the Ute came with a triple chain ring on the cranking end, including a large top gear that should take you up to 30 mph if you feel the need for speed. A handsome seat, dual kickstand, front and rear fenders, and a handlebar-mounted warning bell are other nice touches that enhance a general impression of a bike that hasn’t been nickled-and-dimed to hit a price target. The bike comes with one pannier bag (not shown here). A second will cost $80. Of course, you’ll still need to buy lights, but it’s possible you could hit the road with this bike for under $3000. That’s a few hundred more than the Yuba elMundo, but that’s a very different bike.
On the question of quality, my first concern was the brakes: a rim brake on the front and disc brake on the back. It appears the front rim brake is necessary to make room for the hub motor. It’s not obvious how you could install a disc brake without changing the motor as well.
How critical is a front disc brake? That depends on your situation. If you intend to carry big loads down steep hills, the rim brake will be an issue. The rim on the Ute looks pretty durable, but it’s hard to know how it would wear under heavy use. In my opinion, Kona wasn’t trying to build the ultimate hill-hauling machine with the Ute. If that’s what you’re looking for, there are other bikes to consider.
Motor
Hub motor and rim brake
The Ute’s 250-watt front hub motor looked tiny compared to the 350-watt BionX motor I use. Could a motor this small really help with big loads and big hills? I took it on a ride around the neighborhood to find out.
On flat terrain, the motor behaves much like mine. With these motors assisting your legs, it’s not always clear what gear you should use. Many times you can shift into a higher gear than normal, and the motor makes up the difference in effort. You don’t even have to down-shift when coming to a stop, because the motor will help you start again.
But there were some differences too. Unlike the unusually quiet BionX, the Kona motor always lets you know it’s there. It emits a sound that I can best describe as a moistened finger rubbing across glass – sort of a cat-like mewling. It’s not an unpleasant electric whine, but it’s a noise you probably wouldn’t miss if you turned the motor off and pedaled along without it.
Like my bike, the Kona motor is activated by pedaling, not by a handlebar throttle. There’s always some debate about whether a throttle or pedal activation is better. Since I’m used to pedal activation, I’ll admit being partial to it. Kona says they use a “Dutch design TMM torque sensor” to determine how hard you’re pedaling and how much additional assistance to kick in with the motor. During my ride it worked pretty smoothly, but wasn’t quite as responsive as the BionX system. In some cases, the motor continued to pull for several seconds after I had stopped pedaling. When you apply the brakes, the motor stops immediately, but I’m not sure how it knows to do that.
Another difference is motor vibration. With the motor directly under the handlebars, I felt small vibrations from this motor more distinctly than I do from mine. Is this a showstopper? Not at all. But does it diminish the illusion of bionic legs propelling me smoothly and quietly down the road? Well, yeah.
To test the bike’s hill-climbing abilities, I found a pretty steep section of road – several hundred yards at maybe 15% grade. My first attempt was successful, and the motor provided welcome help on the steep incline. I had to pedal a little harder than my bike, but in hindsight I realize I had the motor set on the middle assistance level. Changing to the highest assistance level might have provided more help. However, a fist-sized hub motor isn’t going to perform miracles. I decided to repeat the experiment so my wife could take some video of it. On my second ascent, the motor suddenly shut off about half-way up the hill. This was disconcerting — I’ve never experienced anything like that with the BionX motor. Thinking I had done something wrong, I made another attempt in a lower gear, but this time the motor was comatose during the entire effort.
Now I was worried that I had damaged something. Fortunately, the motor came back to life on the flat roads back to the bike shop. I am now pretty sure that the controller was purposely shutting down the motor to prevent damage from overheating. Unfortunately, there is no indicator on the Ute’s display that the motor is in an overheated state. Because of that, you’ll worry if it ever happens to you (which it may not). After a little cooling break, everything should return to normal.
Battery / controller
Battery
I’m pretty excited about the Ute’s battery. It is nicely integrated in the bike, and it’s big enough to provide ample range. The battery can be removed and taken to your office for charging, or it can be charged on the bike.
Although I didn’t have time to test it, the combination of a big battery and a small-ish motor should theoretically give the Ute good range on a single battery charge. The rider can adjust the assistance level by quick taps of the power switch behind the handlebar display. Obviously, range will increase with a lighter level of assistance.
The system uses a separate controller box mounted on the main stem above the crank, but it’s smaller and more refined than the Stoke Monkey controller. The handlebar display shows battery status, speed, mileage, and assistance level.
The bike
Handlebar display
Due to the battery cut-out issue, I didn’t have the opportunity to haul a load up a hill. For my purposes, that would have been the most interesting (and most strenuous) part of my test drive. In lieu of that, I put both kids on the cargo deck (about 140 pounds total) and rode some laps around the parking lot. The bike handled this test well — no squeaks, no noticeable flexing, and no balance issues with the heavy load and high center of gravity.
Of course, cruising on this bike is the easy part. Starting and stopping was a slight challenge for me, because I’m accustomed to the low step-down of my Hammer Truck. With the Ute, I have to jump off the seat, tip the bike slightly (not a good idea with kids on the deck), or reach a tip-toe down. Despite a few wobbly moments, I felt pretty stable with the kids on the back.
But I probably wouldn’t make a habit of transporting more than one child on this bike. I carry both kids down our hill on my Hammer Truck, but I keep it slow — around 10 mph. Even with regenerative braking engaged, the brakes can get pretty hot. Attempting that trip with the Ute’s brakes would cause too much anxiety.
Conclusions
The end
Although it has been helpful for me to structure this review using comparisons to my own bike, it’s not entirely fair given the Ute’s significantly lower price. I am personally excited by the Ute’s value and the potential to expand the cargo biking market.
Video review
If you want to see some clips of the bike in action, check out the video version of my review:
Today I took my bike for its first checkup after 7 months and over 500 miles of hill-chewing. As you may recall, I have done no maintenance on this bike other than one application of chain lubricant. Since I rely on it to provide safe transportation for my family, I wanted to ensure that no latent problems were developing.
For the diagnosis, I went to one of Seattle’s pricier bike shops. I deliberately chose a different shop than the one that built my bike, because I wanted a second opinion — especially on those mission-critical brakes. The owner of this shop is a big fan of the Big Dummy/Stoke Monkey bike, and I thought it would be enlightening to talk with someone who is somewhat skeptical of my bike. He has a reputation for pulling no punches, so I prepared myself for some rough sledding.
But actually, things went quite well. The owner found several occasions to point out advantages of the Stoke Monkey, but these were arguments that I’ve written about previously. He complained that the BionX hub motor makes it harder to adjust the rear disc brake calipers, because the hub blocks easy access to the dial that positions the brake pads. He charged me an extra $10 for the additional effort required.
The total bill was $75 for labor. He adjusted and lubed my derailleur to recover my lost gears, cleaned and tuned the brakes, and lubricated various cables. I paid another $25 to upgrade the front brake cable for better responsiveness, but that wasn’t critical. Using the $75 figure for essential maintenance, I calculate a cost of about 15 cents per mile. On the one hand, this figure is probably high due to the difficult geography this bike has to tackle. On the other hand, it’s probably too low on an annualized basis, because I didn’t have to replace any parts this time. In another 6 months, I may have to replace at least one of the disc brake rotors and possibly the pads, but that shouldn’t cost more than $50. As I suspected, the regenerative braking of the BionX motor seems to be extending the life of my brake components. What isn’t clear is how often other components will need to be replaced, and how much that will cost. Although it will be pretty cheap compared to repairs/maintenance of a car, the number of bike miles will also be less, so it remains to be seen which is cheaper on a per-mile basis.
Just to be complete, the electricity to help propel me during this time period averaged about 1/2 cent per mile. Hardly worth mentioning compared to the maintenance.
One sweet moment occurred while I was paying my bill: a customer was admiring my bike and asking questions about it. He was initially attracted by those huge Xtracycle-incompatible pannier bags. He was really intrigued when I told him the bike was assisted by a quiet (and virtually invisible) electric motor. He was standing less than a yard away from the owner’s Big Dummy at the time, but it was my bike that caught his eye. I have no doubt that the owner had him converted to a Big Dummy shortly after I left the shop, but my bike and I had our moment.
I plan to return to the same shop after another 7 months and 500 miles. The owner did a good job and seemed to know what he was doing.
In a previous post I described a canopy that Thea and I made for our Xtracycle to protect her from wind and rain. It looks sort of like a covered wagon on the back of our bike. It was easy to build without special tools or parts, did not require modifying our bike and cost us less than $150 for parts. It weighs about 2 lbs. and we can set it up in less than five minutes. Here’s how to make it.
Materials You Will Need
(1) Xtracycle
(1) 7/8″ x 48″ dowel
(4) 3/4″ long wood screws for the base
(4) #6 x 3/4″ machine screws and nuts
(12) 18″ x .340″ aluminum tent poles with inserts
(2) 18″ x .340″ aluminum tent poles without inserts
(4) 18″ x .626″ aluminum tent poles with inserts
(1) 18 x .625 aluminum tent pole without insert
(4) .340″ 145 degree tent pole elbows (ignore the holes)
3 yards by 60″ of silicon-coated rip-stop nylon cloth
25 feet of light cord
(4) grommets
(4) buckles and 25 ft. of 1/2″ webbing
Tools You Will Need
hand saw
drill (although use a drill press if you have one)
#1024 1.1 OZ SILNYLON 1STS , (Tan)…3 at $9.99 = $29.97
#4060 TENT POLE W/ INS .625 18 inch Black…4 at $4.95 = $19.80
#4061 TENT POLE W/O INS .625 18 inch Black…1 at $3.95 = $3.95
#4018 TENT POLE W/INS. .340 18 inch Black…12 at $2.60 = $31.20
#4019 TENT POLE W/O INS .340 18 inch Black…2 at $2.20 = $4.40
#4055 TENT POLE ARCH-145 DEGREE .340 BLACK…4 at $2.95 = $11.80
#2000 WEBBING- NYLON MED WT 1/2 inch Black..25 at $0.49 = $12.25
#3026 SIDE RELEASE BUCKLES – 1/2 inch…4 at $0.39 = $1.56
#4200 tubing cutter…$7.95
#3235 grommet tool (5/16″)…$10.99
#3231 (10) 5/16 grommets…10 at $0.18 = $1.80
purchase at a hardware store:
(1) 7/8″ x 48″ dowel…$3
(4) 3/4″ long wood screws…$1
(4) #6 x 3/4″ machine screws and nuts…$1
25 feet of light tie-down cord such as cotton clothes line…$5
TOTAL: $145.67
How to Make the Canopy Cover
The rectangular canopy cover fits over the canopy frame and is secured at the bottom with tie-down straps. The front and back of the cover can be cinched up with a drawstring like a covered wagon. If you like, the cover’s size can be adjusted, along with the frame’s pole lengths, for different sizes of passenger. The size I give here is appropriate for a large child or small adult.
1. Cut the cloth so that it is 108″ (3 yards) by 60″. The 60″ edges will be along the sides of the canopy, and the 108″ edges will be the front and back. Hem the 60″ side edges first, then the 108″ front and back edges. Make the hems about 1.5″.
2. Next make the drawstrings. Using a stiff wire as a big sewing needle, insert about 12 feet of cord into the front hem, then repeat for the back hem.
3. Next use the grommet tool to insert two grommets on each 108″ side, about 18″ from the front and back (the video below shows how to use a grommet tool). If you are using thin cloth, reinforce it first with an iron-on patch.
4. Cut four 20″ lengths of webbing for the tie-down straps. For each strap, sew one end of the webbing to the female buckle and thread the other end of the webbing into the male buckle. Thread the straps into each grommet hole.
How to Make the Canopy Frame
The canopy frame “base” consists of two 7/8″ x 24″ wooden dowels that are inserted into the Xtracycle h-rack (horizontal) tubes and secured with wood screws. Aluminum tent poles are then erected upon this base: a front hoop, a rear hoop, and two cross pieces.
1. Cut the 7/8″ x 48″ dowel in half so that you have two 24″ pieces.
2. Drill a 19/64″ hole 1/2″ from each end of each piece. Make the holes as vertical as possible and make them exactly parallel.
3. Insert a base pole into the Xtracycle h-rack, center it, and align the holes so that they are vertical. While holding the base pole in place, drill starter holes for the woodscrews where the h-rack tube has holes in its side.
4. Screw the base poles to the bike with the woodscrews. I just leave the base poles on my bike all the time. The front pole provides a nice footrest for passengers.
5. Next make the hoop poles. All you have to do for this step is cut four of the 18″ poles to 12″ (or a different length depending on your expected passenger size). The video below shows how to use a pipe cutter.
6. Next make the cross pieces from the .625″ poles. For each of the poles that have inserts drill a 11/32″ hole in the ends opposite the inserts, about 1/2″ from the end.
7. For each of the four cross piece ends insert an elbow piece. It may take some effort to get it in and you may have to hit it with a hammer.
8. Drill a 9/64″ hole that goes through the elbow that is in the crosspiece. Screw the elbows into place with the four machine screws.
9. Cut two 6″ pieces from the .625″ tent pole that *doesn’t* have an insert. These will serve as the center parts of the cross pieces.
How to Assemble the Canopy
CAUTION: do not leave your canopy frame uncovered. Without the cover it is only held together by friction. If jostled it could come loose and snap back with surprising force (and for example break a garage window as I learned from experience). DO NOT ride your bike with an uncovered frame (again as I learned from experience you don’t want to be picking up all 20 tent poles in traffic). If you want to use the frame for some purpose other than the Bike Wagon canopy, consider putting a shock cord within it or using external guy wires as I do for using it to support my solar panels.
Final step: do me the courtesy of sending me a photo of your finished canopy!
How to Cut an Aluminum Tent Pole with a Pipe Cutter
How to Add a Grommet to the Canopy Cover
How to Make a Canopy Sack
If you have enough cloth left over you can use it to make a canopy sack.
1. Cut the cloth to 27″ x 20″. Hem the 20″ side.
2. Fold the cloth in half and sew the edge, leaving an opening for the drawstring at the ends of the hem.
I went to the “Sustainable West Seattle Festival” with my family on a rare sunny Saturday afternoon, hoping to see a Kona Electric Ute that a local bike shop was scheduled to show there. It was fun to see many like-minded people showing various sustainable choices — bee keepers selling local honey, farmers selling organic chicken feed for your home-raised chickens, Zip cars, small wind turbines, and various kinds of electric bicycles. Unfortunately, the Ute was not one of them. Apparently, the Kona rep had not gotten a Ute to the bike shop in time for the festival, so this elusive bike foiled my best efforts once again. I know a bike shop in our area that definitely has one, but it’s a bit of a drive and a ferry ride to get there, so I’m hoping to combine that trip with another outing sometime.
If my efforts to see a Ute have been challenging, getting a demo of the Yuba elMundo seems nearly impossible at the moment. There is only one bike shop within 100 miles listed as a Yuba dealer. When I contacted them about the possibility of seeing the elMundo, what I got instead was a strong recommendation to steer clear of this bike as well as the Ute and any other inexpensive cargo bike. The bike dealer recommended the Surly Big Dummy with a Stoke Monkey motor as a superior way to handle our hilly geography. This came as a surprise to me, because the Big Dummy was the bike I first intended to buy, but I was disuaded by several factors. I’ve listed these elsewhere, but the main problems were the size of the bike (my wife wants a bike that is easy to ride) and maintenance of the Stoke Monkey (frequent alignment is necessary to avoid problems with the second chain).
The bike dealer pointed out that the Stoke Monkey is better for climbing hills, because it works through your bike’s gears. In contrast, a hub motor like the BionX applies torque after the gears. When you climb hills, a hub motor is running at low speed where it is inefficient. I can verify that: on the steepest part of my hill where you want the most help, the motor does not feel like it is working as hard as you would like. The bike dealer says his Big Dummy climbs 20% grades (steeper than mine) with less effort than my bike.
So, if you’re serious about replacing your car and hauling big loads up steep hills, the Big Dummy and Stoke Monkey are probably the best choice for you. But unfortunately, it requires a custom build, and it’s a pretty crude system compared to my bike. This video shows what I mean:
Everything demonstrated here seems like it’s a generation behind my bike. The controller and burrito bag seem pretty crude: my controller must be built into the BionX battery case, which is beatifully mounted under my cargo deck. Putting that big battery in the XtraCycle bag seemed primitive in comparison. I could go on, but you can watch the videos and form your own opinions. (If you haven’t seen my bike video, it’s here.)
I hesitate to criticize the Big Dummy and Stoke Monkey, because it’s a great bike and people have done a lot of amazing things with it. For example, the BikeForth.org blog is one of my favorites — the author is pushing the boundaries of car replacement with weather coverings and solar power for his Big Dummy. It’s really great stuff, but I sometimes feel like he’s quite a bit ahead of his time. My practical side is struggling to find ways to get more people on bikes, even if only for some of their trips. I would love to jump directly into a future where bikes are as prevalent in my country as they are in Denmark, but to enable that future we have to find a way to make our bikes more mainstream. I feel like my bike is closer to that practical ideal than the Big Dummy/Stoke Monkey, but the price is still a barrier unless you’re completely replacing a car. Even as a cargo biking advocate, I still drive our mini-van, frequently. With our current infrastructure and suburban location, it’s not possible for me to transport my busy family without the car at this time. So the cost of the bike comes on top of the cost for the car, and that is a challenge for many family budgets.
On the other hand, I don’t want to recommend the Ute or the elMundo if their inexpensive price comes at the cost of reliability, functionality, or safety. Until I see them first-hand, or a good bike magazine does a thorough review and comparison of them, I can’t say if these are good candidates for advancing the worthy cause of cargo biking.
I’ve been debating for weeks whether I should include any mention of the Gulf oil spill in this blog. On the one hand, my desire to minimize our impact on the environment is a major motivation for my cargo biking activities. On the other hand, I’m not sure I can say anything new or relevant about the situation. With hourly updates on the containment of the spill (or lack of any real progress), you’ve probably heard all you need on the topic.
But if you haven’t seen this site (http://www.ifitwasmyhome.com/), you should. It moves the oil slick to your neighborhood to give you a more visceral appreciation of the scale of the calamity. In my state, the slick covered all of the Olympic National Park, Rainier National Park, North Cascades National Park, Puget Sound, and most of Washington’s coast line:
Imagining all that beautiful scenery fouled with mats of smelly oil is heartbreaking. But no less than what Gulf state residents feel about the waters near their homes.
If you want to read more about a cargo biker’s take on the spill, here’s an article that says everything I wanted to say, only better: http://bikeforth.org/dont-blame-bp-blame-me/
The ElectraFlyer ultralight. Note the guy wires. Its electric motor weighs twice as much as my Stokemonkey motor (26 vs. 13 pounds) but it has 18 times the horsepower. The battery weighs 6.5 times my 36v 10ah Prismatic LiFePo4 (78 pounds vs. 12 pounds) but produces about 10 times the power. An Xtracycle with this monster motor and battery would add 104 pounds to the bike but would increase the range to 250 miles. Add that wing, throw in a propeller and my Xtracycle could fly!
Thomas Morse Scout showing guy wires. Incidentally this plane was manufactured in Ithaca the small town where I live.
I’ve been trying to wrap my head around guy wires. No that doesn’t mean wires made by guys. It means a tensioned cable used to brace parts of a structure or vehicle. For example have you ever noticed the cables forming Xs between an old biplanes’ wings? Those cables prevented the two wings from moving relative to each other. They also made it possible for a biplane to be lightweight. As biplanes’ motors became more powerful weight has not been so much of a factor and you don’t see as many or any cables on a modern biplane. However you do see cables on ultralight aircraft as shown. More and more you see cables used in architecture. I argue that we need to use more cables—and parts under tension in general—in the design of our cars.
Guy wires to stabilize my solar canopy.
I recently needed to add guy wires to my Bike Wagon canopy design because when I put my solar panels on top of the canopy, the added weight made the canopy wobbly. A few cable Xs solved the problem. It got me thinking about how the design of ultralight airplanes and bicycles and lightweight vehicles in general requires using tensegrity. Say what? “Tensegrity” is a word that American architect and inventor Buckminster Fuller made up by combining the word “tension” with the word “integrity” to describe a new building technique. The basic idea is that you can make way cool lightweight structures by combining something with structural integrity (such as a hunting bow) with something that is under tension (such as the bow string).Tensegrity structures can have the unnerving property that the beams of the structure don’t actually touch each other (see the Tensegritoy below). Our bodies themselves use tensegrity: our bones provide the structural integrity and our ligaments and muscles provide the tension.
A wonderful way to get hands-on experience with tensegrity is to order a Tensegritoy kit.
The bicycle wheel is another good example of tensegrity. Back in the day wheels were constructed using wooden spokes. The spokes needed to be thick and heavy. The bicycle wheel, in contrast, uses tensegrity. The rim provides the structural integrity and the spokes provide the tension. This design creates a very strong lightweight wheel. A car wheel (excepting the occasional MG) does not use tensegrity; it is solid metal. A car’s large powerful internal combustion engine overwhelms any need for weight savings. Incidentally there are commercially successful bike frames that use tensegrity.
The Millenium Dome in London is constructed out of steel towers and tensioned fabric.
Tensegrity is a revelation in architecture. The first large buildings relied on gravity and the compression strength of stone to hold themselves up. Then with the invention of the steel I-beam, buildings could use the structural integrity of the I-beams to hold themselves up. More and more architects are experimenting with tension components such as steel cables and fabric. Some of these structures are what the layman would call a tent. However, we’re talking tents that are very large permanent structures such as the 1,200 ft. wide (365 m) Millennium Dome. Two related ideas are tensile structures (elements carrying only tension and no compression or bending) and tensairity structures (pneumatic structures that use inflated airbeams and attached stiffeners or cables).
Buckminster Fuller's Dymaxion Car. It was about 6 feet tall, seated the driver and 10 passengers, weighed less than 1000 lbs., went 120 miles/hr on a 90 horsepower engine, and got between 30-50 miles to the gallon of gas!
I believe road vehicles need to undergo a similar transition—from compression to tension components in their construction—so that they can become light enough to be powered by humans and by sunlight. Contemporary cars have structural integrity mainly by virtue of the strength of steel. I envision lightweight slow small vehicles that use aluminum poles, cables, and fabric to give them shape. Is this possible? It can’t hurt to dream big. In 1930 Buckminster Fuller’s own car invention, the Dymaxion Car, weighed less than 1000 pounds and could carry 10 passengers.
click photo to see charger, connector and battery highlighted on Flickr
A lot of people ask how the electric cargo bike charges, so I thought I would post a photo.
It’s essentially the same process you would use with rechargable digital camera batteries, only with a bigger battery and a bigger charger.
Our LiFePO4 battery is size of a miniature loaf of bread and can be easily unplugged from the bike and plugged into a charger. The claim is that this needs to be done every 15 to 35 miles. Based on our usage, it appears that it may be more like 30 to 50 miles. (Because we don’t always engage the electric assist).
It turned out I had a rather ideal situation in my garage, with a electrical outlet directly above where we usually park the bike. So, here you can see our charger mounted to a pole, and the battery is literally just “plugged in” with an XLR connector while still attached to the bike.
With this battery it’s also healthy for it to keep it fully charged, so we can simply plug it in when the last ride for the day is done. Because the range exceeds our daily needs, this process implies that the electric assist is always available when we need it.
In sum, it takes just seconds to charge at an estimated of cost of less than a penny per mile. By contrast, I once calculated the total cost of operating my wife’s station wagon. It worked out that to require about one hour of work for to pay for every one hour of driving the car. That’s not exactly efficient if you factor all the money-earning time into your True MPH for driving your car.
If you are curious about your own true average speed in your vehicle you can download a spreadsheet I made to calculate it for yourself.
Just for fun, here are a few numbers I measured this morning, in an effort to make my blog a little more precise:
70 pounds — the unloaded weight of my Hammer Truck, battery, motor, bags, lights, etc. That’s actually somewhat heavier than I expected. And that doesn’t include the canvas shopping bags, rain cover, bike lock, water bottle, bungee cords, and other things I keep in the side bags for easy access. No wonder I feel a little weak when I turn off the motor (only occasionally) and try pedaling up our hill.
30 pounds – the weight of my non-powered bicycle for comparison. But I almost never ride it if the cargo bike is available.
10% grade – the incline of the road in front of our house.
18% grade – the incline on the steepest section of road on our way to school every morning. It lasts for about 100 yards. When I’m hauling a 70-pound kid and 20 pounds of books and instruments up that part of the hill, the motor and the human are both close to their limits. This is when you begin to appreciate the miracle of cars. Just press that accelerator a bit more towards the floor, and 10 times the mass of my load leaps up the hill at 5 times the speed. But that challenge only lasts for 100 yards, and most people don’t have 18% inclines in their daily routes. The 10% grade feels more reasonable, as you can see in the first part of my Electric Cargo Bike video (http://mycargobike.net/2010/05/06/cargo-bike-video), where I haul my son and his stuff around the corner and up the hill.
7 months — the length of time I’ve been riding my bike down that hill, often with two kids as passengers, without any brake replacements or adjustments. I think that is the best aspect of the BionX regenerative braking system. I’m just beginning to think that an adjustment might be necessary in the next month or two. My wife wore the brake pads on her traditional bike down to the metal in that same span of time.
Good news: I’ve found an owner as well as two local bike shops who have the Kona Electric Ute. I hope to take it for a test drive this weekend at a local sustainability faire!
