I had the chance to attend the bike industry’s annual DealerCamp in my hometown of Park City, Utah last week. It’s an event where dealers and manufacturers can meet up, and everyone can try the latest bicycle technology on the roads and trails. While there, I took a particular interest in electric bicycles, which were represented by several vendors. Electric bicycle tech has made some major strides in the past few years, but still has a long way to go, in particular on the software side.Pretty much since their inception, electric bicycles have been characterized by sketchy-looking self-conversion kits and uninspired if not downright bizarre-looking bicycles. All of them, of course, aimed at smooth pavement riding and commuters. So when I walked by the BionX booth and saw and electric conversion of one of the craziest and coolest looking bikes available, I was immediately interested. I’m a die-hard mountain biker, and don’t have much use for road bikes of any stripe, so I’m a bit biased, but I think anyone’s head would be turned by what I saw.
It was the incomparable Surly Pugsley, a mountain bike with huge, oversized rims and tires, ostensibly designed for riding on snow, sand, and other soft terrain, but really designed just to be awesome looking. Its rear hub was built up with the PL 350HT SL XL brushless electric motor, and it had a big battery pack attached to the frame. On the handlebar was a console that looked like a conventional bike computer/speedometer, only larger.
I took this bike for a spin up a pretty serious mountain biking trail near Deer Valley, and I had a smile plastered on my face the whole time. It was about the most fun I’ve ever had on two wheels, and I have ridden some of the most amazing and famous mountain biking trails in the world.
This latest-generation electric hub motor isn’t designed to be able to propel a bike uphill on its own. You can think of it like a hybrid car, only instead of supplemented by a gas engine, it’s supplemented by the rider’s pedaling. While riding uphill, I pedaled steadily, and the motor supplemented my efforts. The amount of ^aEURoehelp^aEUR was configurable by hitting the + or – buttons on the console, or on a thumb control keypad next to my right grip. I kept it set to ^aEURoefour bars^aEUR the whole time, which was the maximum amount of boost.
It also features regenerative braking, so while I was watching the battery indicator diminish as I was going up, I got it to recharge a bit on the way down. Unfortunately, most of my downhill was steep enough that I was also riding the brakes. I kept thinking, ^aEURoewhat a waste of good potential energy!^aEUR
It was a hot summer day, and I was dressed for the office, which in my case was jeans, an under-shirt, and a short-sleeved button-down shirt. I rode steadily uphill into the mountains until the tents and vehicles in the parking lot below looked like toys. Normally, after fifteen minutes of riding like that, I’d be drenched in sweat, dressed as I was. But in this case, my pedaling was light enough that I felt as fresh as I would if I’d been strolling slowly along those shady mountainside trails. If I’d rolled up to my office, I would have been able to sit right down, with no shower necessary.
The Surly Pugsley is not the most efficient of mountain bikes. It’s a novelty act. Its big wheels take a lot of effort to keep rolling, but its big tires and low air pressure make for a comfortable roll, and I was tearing up and down the switchbacks. The electric boost made what would have been a slog into a joy. I also ride motorcycles sometimes, but this ride was completely unlike riding a motorcycle. Despite the 14 pounds of extra weight for the motor and battery, the bike felt lighter and more maneuverable than any motorbike, and it didn’t propel me along. It felt like bicycling, only easier. And of course it was completely silent.
As fun as it was to ride on the trail, it was just as fun to ride around the roads. I was able to easily ride up a flight of 12 stairs. I kept thinking that even being an off road bike, the motorized Pugsley would be a blast to ride around town every day.
But while I was riding along, I was also cataloging the bike’s shortcomings. There are the obvious ones: the motor, and especially the battery, are much bulkier and heavier than I wish they would be. Adding 14 pounds to an already-heavy 35 pound bike makes it downright bulky. Having the option of putting out more torque for a bigger boost would be nice, though it would obviously eat up battery power. And as I mentioned, the regenerative braking wasn’t up to the downhill speeds I was reaching.
And of course, what dashed my dreams of buying the motorized Pugsley was the price. The motor and battery kit is about $2100. Possibly justifiable if I were to buy it for an everyday commute, but impractical for a recreational trifle.
But I think some of the most interesting improvements to this bike, and all electric bikes, could be made in software. I’m hopeful that in the next decade, along with advances in battery technology that every smartphone owner has already been pining for, we could see electric bikes get a lot smarter, and therefore more practical, and more popular.
The BionX system isn’t just a dumb motor with an on/off switch. As they describe it, ^aEURoeEnergy is provided in proportion to the torque applied to the pedals: Pedal harder and get a stronger and faster assistance, pedal lightly and receive gentle, gradual assistance. Stop pedaling and your assistance is automatically cut off. Each pedal stroke is analyzed separately by a microprocessor, equalizing your energy so you can concentrate on enjoying a smooth, powerful and precise ride.^aEUR I could feel that the boost was adjusting as I modulated my pedaling effort.
The BionX system’s regenerative braking was something that I was very excited about. Because of the mountainous area I live in, I often have long, steady descents, and it would be great to be able to generate electricity. Unfortunately, you’re not going to be able to ride bike up the hill, and have the ride down power you back up. For various reasons, the regeneration doesn’t recover a substantial amount of your energy. On topsy-turvy sections, I wasn’t able to reap the full benefit of either mode (boost or regeneration) because you have to be moving at a certain speed before the boost kicks in, and you have to actively engage the regeneration, either by hitting the rear brake gently or by setting it on the console. There were times when I was burning battery and spinning the hub when I didn’t need to, and likewise times where I was heading downhill and not recovering electricity, or recovering less than I could have.
The BionX system does monitor some data and adjust accordingly, but I think there’s room for improvement. For forward momentum it would take very little computing power and a few sensors to be able to calculate the various inputs (speed, incline, pedaling speed and torque, alteration in pedaling cadence, the accelerometer graph) and calculate an optimal amount of boost for each condition, second-by-second. Individual settings could be fine-tuned, with a rider’s preferred speed at various levels of incline and relative pedaling effort. The system could even be set to learn those preferences in a special mode. Managing the motor’s function more carefully could save energy. Also, with the conditions being monitored by software, the regenerative braking could be applied much more liberally, recharging the batteries more.
With a powerful-enough motor and smarter systems, it might be possible to simplify the bike’s mechanical systems to make the bike lighter, more foolproof and easier to maintain. The bike I was riding had a conventional mountain bike drivetrain with a 27 speed derailleur setup. That’s necessary to provide a low enough gear for climbing, but a high gear for riding fast on flat ground. A powerful motor might be able to make it practical to use a simple single-speed drivetrain, and possibly even eliminate the rear disk brake entirely, by supplementing the rider’s pedaling with motor power efficiently, and using only the motor to slow the rear wheel while braking.
While I was riding, I was also wondering whether it would be feasible to do a completely drive by wire system wherein the pedaling only charges the battery, and isn’t connected physically to the wheel at all, similar to the way that some heavy equipment uses a large diesel powerplant to generate electricity to electric motors, and does away with a mechanical drivetrain altogether. Would that result in unacceptable inefficiency? Maybe that would require a motor that’s more large and powerful than would be practical.
Throw in some other mobile computing capabilities, and things can get really interesting. A GPS receiver and Wi-Fi (to pull down data while you’re at home) could enable the onboard systems to recognize a trail or road that you or some other user has ridden before, and implement a power profile that anticipates every hill with perfect precision, not only applying motor power and braking efficiently, but being able to indicate exactly what point on the trail ahead it will run out of battery power. And of course, it would be nice to have a usb charging slot on your bike when your phone loses power, not to mention some built-in LED lighting for the night time.
Many serious cyclists are sure to scoff at the thought of motorized cycling in any context other than commuting and tooling around town. I’m sure that if the people I passed on the trail had known I was on a motorized bike some would have looked askance. There’s a feeling that if you’re going to be on the trail, you need to deserve to be there, by working for it. And of course one of the most popular reasons for recreational cycling is exercise. But the truth is that serious cyclists spend thousands of dollars on their bikes to trim a few grams here and there, all so they can get up the hill and not have to work as hard. Is that cheating? Does the guy with the $4000 bike deserve to be there any less than the guy on the $200 beater because he’s got it easier? As long as motorized bike users aren’t going any faster and aren’t making any other noise than other cyclists on the trail, then it shouldn’t make a difference.
The truth is, most people who shun cycling do it for one simple reason: it takes too much effort. If you remove some of the effort, you get more people on bikes. And while riding an electric bike creates more pollution than riding a regular bike, it’s a hell of a lot less than driving a car, or even taking a bus. I’d suspect that riding an electric bike for an hour takes less electricity than watching a plasma TV for an hour.
The more people you get on electric bikes, the prices for the equipment does down. The $2100 kit I rode probably has similar technology to the high-powered cordless circular saw I own. But the saw costs about $400, because it’s produced in high volumes by a large international conglomerate in a brisk competitive marketplace. The bike kit is manufactured in small volumes by a specialty outfit. I for one am really looking forward to a future where electric bicycles are smarter, lighter, and cheaper, and therefore much more popular.
Fun stuff! 35(+14) pounds does seem heavy for a bike designed for slogging up and down hills on rough trails.
For $2100 you could purchase a decent, used on/off road motorcycle (tho’ I understand it is totally different from the type of travel a die-hard off-road mountain biker would consider)… saves fuel from a car and you can still take it off-road a bit.
I love watching my wife’s charge indicator screen on her prius as we travel up and down mountains and valleys.
She makes a game out of it, trying to reach over 50 MPG.
[edit]
…and having programmed hand held devices and portable software before, designed to run on multiple computers, I can bet the guy who wrote the adaptive software had a lot of fun!
Edited 2011-08-01 17:33 UTC
Indeed. And in fact the most recent motorcycle I owned bears a striking resemblance to the Surly. The Yamaha TW200. It’s very good, inexpensive, and practical motorcycle, which is also crazy-looking: http://www.yamaha-motor.com/sport/products/modelhome/10/home.aspx
I like that!
…and does away with a mechanical drivetrain altogether…
I have thought that this would be a good way to do as well. (For cars as well as bikes)
I bike to work a lot of the time, but there is a valley I have to go through from home to work. So work and home I end up sweaty. (I go to work early enough that it is not a problem, but the way home in the summer is bad.)
Commuting on a bike that I could provide some supplementary electric charging to, but not much of a sweat would be great as some places I have worked I cannot really arrive sweaty.
I’d have to say that arriving at work sweaty is probably the #1 thing keeping people who would otherwise like to commute by bike from doing so. More than having to bike in cold or rainy weather. In fact, a lot of the places where people bike a lot (Portland Oregon, The Netherlands) aren’t exactly known for their beautiful weather. But you don’t see too many Bike commuters during a Phoenix summer.
Yep, I’m in the Netherlands and I go to work every day, all year round on my bike. We have a lot of good facilities for bicycles and most of the land is pretty flat. So easy riding…
I have to be really careful not to go to fast in summer or I’ll get sweaty.
Problem is I really like going fast.
I agree completely, another reason is I am not supposed to wear shorts to work and pants brush against the sprocket and get greasy.
This is a problem I can solve with a single elastic strap but the problem of getting to work sweaty is harder to solve.
Many companies try to be green, but not so green that they will let bike commuters show up in shorts on a hot day
Might I suggest… having two different pants at hand?
(plus, maybe, different approach to cycling, the one I mention at the beginning of one too long post nearby)
Hm, I’d say that this #1 thing (and particularly the almost closing thought
from the article) is probably partly due to people having the wrong idea about city / commute / daily bike riding, what it’s about. Which for me is to NOT exercise more than during a mere moderately energetic walk – but, thanks to the bike, travelling ~3x faster (like during fastest reasonable sprint on foot); the bonus workout being just of the “mild but regular, healthy” kind.
You also write:
So… why waste the potential?
With how you’re able to really push the bike, some commuting speeds & style of riding should be even less of an issue 
(and that bike is fugly 
…so, if anything, I would possibly turn my head in the other direction; but that’s my bias, my fairly standard opinion about anything “really trying to look cool”; and not only because often the focus on looks means compromises elsewhere, also how it reveals a desire to “trick” the recipients, and often results in caricatures of harmonious proportions & design; BTW, one hilarious example of that in related field, cars, even if in sort of opposite direction: the thinner after-market tires are way too often less efficient / “dynamic” / etc.)
It would be, possibly, also relatively comparable to an everyday bike with more sensible frame, wheels, tires, without the electric motor?…*
*…and which almost starts at an order of magnitude less cost.
Chief one among those reasons: that would be pretty much a perpetuum mobile
(of the 2nd kind at least)
“Drive be wire” (etc.) tends to refer to how steering is transferred; what you mention seems to go nowadays by the name of “serial hybrid” – and yeah, probably introducing inefficiencies disproportional to the power levels of humans, to the type & how we do movement (plus our muscles are fairly efficient at different power levels, I think, so one of the major IC engine problems supposedly solved by serial hybrids also largely isn’t there; also I’m not sure if a bike would feel & drive good with such level of “decoupling” from the road)
For a bus, I probably would prefer to see some numbers before stating anything with certainty… (with a comparably modern bus, maybe a hybrid one / etc., not some old type; just like it’s not about 2-stroke motorised bikes and mopeds of old times)
And coming back to the first thing I quoted – shunning seems to be ingrained on other dimensions of culture, public perceptions…
http://laist.com/2010/08/03/in_hollywood_living_car-free_means.php
http://www.slate.com/id/2262214/
Those are of course also the results of how cars were allowed, for a long time, to hijack urban areas, their layout and planning. The few places with lots of bikes that you mention, also tend to have less urban sprawl; people there sort of didn’t allow for cars to hijack their cities to such a degree; they are willing to set up their life (where they live, how far to work, how and when the shopping or social venues) not as dictated by a car.
PS. A sort of “hub & spoke” model, but with car & bike respectively, might be a useful intermediate approach in some cases. Especially when carrying a (moderately folding) bike in the trunk isn’t much of a problem even with a supermini (and in larger, quick release locks on the front bike wheel might be almost enough)
Edited 2011-08-07 00:53 UTC
There is no need whatsoever for clever software to modulate the amount of power the motor provides – it is a problem long solved on motorcycles by using a device consisting of one tube and one cable… it’s called the throttle.
Yes, but on a bike like this, you don’t use a throttle. If you did, it would actually be pretty hard to use just the right amount of power to supplement your pedaling without eating up the battery too fast.
An electric bike doesn’t have to break the bank. I’ve had a sub-$400 izip electric bike bought through Walmart which I’ve put hundreds of miles on in the past two years. I can honestly say that it has probably saved my wife and I from needing a second car.
I have been wondering for ages why electric bikes aren’t cheaper. You can buy full sized mountain bikes with front and back suspension now for $90 at Walmart.
Small electric motors are very cheap to make and it takes a very small amount of power to help you along.
An $80 weed trimmer (gas or electric) would produce enough power.
With all these advancements in technology I am amazed that combining these things is still so bloody expensive. It should cost $250 to combine a $90 bicycle with the engine from an $80 weed trimmer, not $3,000
Their is two major components you left out… batteries and electronic controller. A controller should be under $100.
However batteries are still not cheap. Realistically you would be looking around $800 – $1500 for a good sized battery pack for off road rough terrain. $300 to $500 for commuting…
So Commuting…
90 + 80 + 100 + 300 = $570 for a cheap commuter…
and that is about what the go for. EG http://www.value-e-bikes.com.au/
Now the mountain bikes (serious ones) start at around $800 or more for the base bike.
800 + 80 + 100 + 800 = $1780 for the cheapest “good” off roader…
and again you can get them for that. EG http://www.hi-powercycles.com/category.sc?categoryId=10
Do yourself a favour and stay away from those cheap made in china e-bikes, as they are complete crap and when they break, no repair shop will touch them… believe me, I speak from experience!
Either splurge 2,000+ bucks for a decent model with decent dealer support, or roughly for the same money get a scooter/second hand motorcycle – much more useful proposition. Again, speaking from experience.
Totally agree… I was just showing that starting with a cheap china frame, with a cheap china motor is not the whole story.
The eZips/iZips sold in Walmart and Target are the low end brands of the American company Currie Technologies which also make $2k+ models and has a dealer and service network. My iZip is built like a tank.
Like most other things from China, but..
Electric bikes are currently extremely popular in China. Basically everything from converted rusty tricycles, city bicycles, scooters to small motorcycles is now using electric motors. Of course they are all used for commuting, not riding in the forest for fun, so they are usually simple, cheap and functional. But there are literally millions of them on the streets, now.
If that trend continues, in a couple of years Chinese makers will be way ahead of anyone else, so I wouldn’t dismiss their bikes just because they are currently designed for Chinese commuters.
braddock teased with…
oi! You can’t just drop that in a conversation on the Internet without putting a link in so we can give it a look ourselves!
–bornagainpenguin
A 50cc 2 stroke scooter is cheaper, much faster (50-70km/h), has a 200+km range, has a much better carrying capacity and is far more comfortable.
Maybe they are trying to reduce pollution, get in a better shape, improve their health, etc. while they go to work, for example.
You get no health benefit unless you pedal the bike yourself.
Batteries have a short effective lifespan (~1000 charges). Processing rare earths to make electric motor magnets is extremely hazardous and highly polluting.
They are talking about pedalling and also using the motor when needed, for example riding uphill. And about the chance of getting batteries charged when riding downhill. They would do exercise but not too much, so they wouldn’t go to work exhausted or with a lot of sweat.
If the destination place is near, they don’t need an electric bike, of course, just a normal one.
Other vehicles, like cars, to be made and to be used… require a lot of elements and have also batteries. I was are not talking about eliminating pollution, just about reducing it.
Edited 2011-08-02 09:18 UTC
Switching to vespa style scooters instead of cars would also be a huge step in reducing fuel consumption and pollution. With our lazy population, it would also be more likely to be accepted. I was looking at moving to a small town and downgrading from car to vespa, but it just wasn’t the right fit for me.
Relatively more likely, maybe. But don’t keep your hopes too high for the place, considering even supermini cars aren’t exactly accepted.
Most lithium batteries quote well over 1000 cycles to loose only 20 percent of their original capacity. They still work just 80% of original energy storage.
Most push bike motors use NO rare earth metals they are just too dear. And most of the concern with rare earth elements in batteries are derived from the Toyota’s NiCd batteries… not newer LiPo or LiFePo batteries.
You do know he was using a mountain bike in forest trails. I don’t think the cheap scooter would do that.
I’ve got a bionx on one of my bikes. I like the system, and for braking I almost only use the regenerative brake.. (I live near Antwerp, Belgium, so it’s quite flat). The system certainly doesn’t work perfectly, but when you’re used to it it is very nice.
Last Spezialradmesse I could test ride a couple of bikes with a system from Bosch, that one really works like a charm. There is no regenerative braking, but the (software of that) system really works good.
Talking about software: the gocycle even has a plug for usb to install updates! ( http://www.gocycle.com/ )
Edited 2011-08-02 09:38 UTC
In the UK electric bikes can only assist your pedalling
http://www.electricbicycles.co.uk/uk-laws.php
otherwise they would be classed as motor bikes.
but they make cycling feasible in a lot of cases that it otherwise would not be. so it may not be as much exercise as a normal bike, or as fast as a motor bike. but for some people it can replace a car, which is a huge saving (cost and energy).
“While I was riding, I was also wondering whether it would be feasible to do a completely drive by wire system wherein the pedaling only charges the battery, and isn^aEURTMt connected physically to the wheel at all, similar to the way …”
What you forgot here is that battery charge while riding is always achieved thanks to the motor, which produces electricity when rotated by mechanical forces. If you want to pedal to charge the battery while not using the existing motor then you need to add a generator, that is another electric motor. And BOTH would have to be big enough to generate enough energy for the whole propulsion. That’s the point after all.
You MIGHT gain a slight improvement in efficiency in energy conversion over a transmission chain (which is not the best of trade but has many other benefits), but I’d bet on a huge overall efficiency loss due to the added weigth. And you’d still have to use the first motor for regenerative braking anyway.
The example you give are of fixed powerplants with no weigth constraints, where mechanical transmission of energy can prove less than practical. Different needs, different contexts lead to different designs.
Dave, I seldom post here but read OSAlert often. I can save all of you a bunch of time with one single link. I’ve spent thousands of hours since 1997 researching this topic and subsequently building eBikes from kits. If you’re really interested in the cutting edge of eBike technology today at far more reasonable prices than the Bionix kits, with all the replacement parts you need, the link below will provide you with a fast-track to becoming current on the topic. Including your desired motor/trip control computer with customizable firmware. This Canadian company is the preeminent kit eBike company that everyone tries to copy.
http://www.ebikes.ca/index.shtml
eBike Law:
Here in the US there is a federal law that supersedes all state laws regarding the classification of eBikes. By law they don’t need a drivers license, minimum age or registration of any kind if the bike has pedals and is kept within the various legal wattage and speed limits set out in the legislation. Here in the states you can have a full power from a dead start version and don’t need to have the pedal assist-only versions required in the UK.
Practical Exercise:
They say the best exercise for you is the one that you’ll do. With an eBike the hills are flattened, thereby making them far more viable a solution for more people. Where I live the old joke about the gran-dad who had to walk barefoot five miles to school everyday, uphill both ways is the real deal. I live on a river at the base of a mountain valley where everywhere you go of any distance is truly uphill both ways.
Regenerative Braking:
Regen braking, while still quite useful, will not ever reclaim much more than 20% of the energy available during braking due to the internal forward resistance inherent in all current battery technologies.
Also, with hub motors the shaft is held stationary while the whole motor turns. Regen braking causes both a positive (when powering) and negative (when braking) torque to be applied to the motor’s shaft the effect of which causes the wheel fasteners to become loose over time. A torque washer is normally used and adequate for non-regen setups. A special torque clamping system is needed for this problem. The reason I mention it here is that the company at the link above hasn’t as yet figured it through fully in that regard. I have been fabricating my own design for some time now because allowing a situation where bolts come loose all the time is poor design.
I don’t have any ties to this company. Just trying to set any of you interested parties on the right track to save you some of the time and aggravation I’ve gone through. Questions?