Electric - Human Hybrid Bicycles

[EricGo]

This topic comes up periodically in PriusChat, but I'd like to hear everybody's most recent experiences and gossip.

Most importantly, I am looking for a model that augments human effort, and not isolated dual powertrains that discourages pedalling.

[EricGo]

This looks promising:
http://www.bionx.ca/en/main/default/31.shtml

Any experiences ?

[LMA]

No personal experience with them, but my understanding is that the big drawback to an electric bike is that the things are *incredibly* heavy (the one I saw brought into my store's bike shop was at *least* 50 pounds) so you end up needing to use the motor on anything but the flattest, flattest surface because you're hauling so much extra weight.

[daniel]

I also have no experience with these, but I imagine it would be harder to balance because of the added weight. Plus, the power would be limited by the amount of weight you are willing to carry. I suspect that, as LMA says, if you have enough power to do any real good, you would have to use it all the time because otherwise the weight would make it too difficult to pedal.

Before hurting my knee, I had a mountain bike which I could ride about 20 miles before being exhausted. I ended up trading it in on a lightweight (but not exotic materials) bike, which I was immediately able to ride 50 or 60 miles, and that same season rode several 100-mile rides. My point is that simply getting a lighter bike with less rolling resistance is probably a better idea than adding the weight of a motor.

On the other hand, the company you link to in your post mentions using their system on trikes. With the balance issue off the table, you could install significantly more capacity on a trike, consider the pedals as merely a small additional assist, and have a human-electric hybrid vehicle for short trips in good weather.

I find it telling that their web site says nothing at all about the range of a bike or trike fitted with their system.

[EricGo]

Daniel, there is a table that shows range as functions of battery capacity and assist level.

Heavier bikes tend to be outfitted with knobbier, wider tyres, which I suspect is the culprit behind LMA's experience, and not the extra weight of the system. One might be inclined to argue that since the electrical systems are put on heavier bikes with those kind of tyres, the end result is the same.

And this might be true for the flat road cyclist hoping to ride in the 25 mph range or faster, but may not hold for the lower speed rider who just wants to 'flatten' out uphill rides -- like me.

[hyo silver]

I've ridden several electric bicycles, but none that would cause me to give up any of my trusty steeds. The weight and the ridiculous speed limit of 30kmh are the killers for me. To paraphrase Scientific American from about 30 years ago: "A man on a bicycle is more efficient at turning energy into motion than any other machine or animal." Some people think electric bikes are great, and I'm not going to take that away from them, but the current modern bicycle is getting harder and harder to improve upon. If and when batteries are lightweight and powerful enough to replace the 'energy storage system' I already have, then sign me up. Another thirty years should do it - the technology will be that much better, and I'll be that much older and slower.

[EricGo]

hyo silver, thanks for chiming in.

I was under the impression that the electric motor was throttled to 30 kph, not the bicycle. Am I mistaken ?

Was the electric bike system effective as a hill 'flattener' ?

[hyo silver]

Hi, Eric. The best one I've ridden, and I'm sorry, I've forgotten the brand, has a variable power assist that can either replace your power or augment it. On the 'boost' settings, my power was amplified a little or alot, as long as I kept pedalling, which was pretty neat. It also had a 'charge' feature that would detour some pedal power to the batteries. The few small hills I tried it on were quicker at first, but anything like a mountain pass will leave you with way too much dead weight that wants a free ride.

I'm not certain about the bicycle/motor speed limit issue. I could tell the officer I wasn't really speeding because the motor was off, but I don't think it would do much good.

[vuapplepudding]

<div class='quotetop'>QUOTE(EricGo @ Oct 15 2006, 10:59 AM) [snapback]332994[/snapback]</div>

This topic comes up periodically in PriusChat, but I'd like to hear everybody's most recent experiences and gossip.

Most importantly, I am looking for a model that augments human effort, and not isolated dual powertrains that discourages pedalling.
[/b]

EricGo,

My electric bike encourages me to get out and exercise. I get bored easily and this thing can get me to places I would never do on human power alone.

Make sure that your city ordinance will allow electric bike on the trails or on the streets first otherwise it is useless. Some cities base it on the wattage.

I have the 36 volt electric bike conversion kit. It works great in my town because I do not enjoy riding up the hilly terrain. With the 36 volt kit, I can use the battery to help me up those hills (while still pedaling a little to save the battery). Easily pulls 210 lbs person up a 20 degree grade at 5 mph with no assistance. It is hard on the motor and drains the battery more. You must have a good front fork and the space between the forks important so follow the installation instructions closely. I had to spread my forks a little. I checks for cracks on occasion.

Then on flat surfaces I just ride like usual. I pull my son on a bike trailer and it is really helpful on the windy days. That little trailer has a ton of drag. By using the battery mainly for hills I can go for a long time.

These batteries are heavy and awkward since the rear bike rack places the heavy batteries high on the bike. This makes balance a challenge. Not suggested for those that cannot mount a bike easily. NiMH batteries are an option but very expensive. The front wheel relatively heavy compared to my aluminum rims.

My batteries charge in about 2 - 3 hours if fully discharged. I suggest that you do not fully discharge this since they are sealed lead acid. Deep cycles will shorten the life.

Still I am happy with it since I am young and willing to use the technology to get myself out to exercise. Otherwise a normal bike just sits in the corner of the garage.

As an alternative, I have considered buying a second bike with the battery mounted much lower to the ground. http://www.rmartinbikes.com/.
For a little more money you do not have to retro-fit your current bike.
I like the L780 since it has 48 volts and would ride more like a moped (tons of power not doubt about it). But the bike trails would not allow a moped looking bike on the trails so I might have to consider the L580. Notice the battery is mounted lower and more centered. This will make balancing much more manageable.
They also have REGENERATIVE braking. PRIUS owners will love that. Not sure how efficient this would be though. I am sure you will not recover the same as the advanced PRIUS.

Another alternate is the e-bike brand. They are nice but expensive. If you are willing to pay the price, this is the way I would go.

I have also seen the military version of the e-bike that used NiMH batteries that are in the bike frame. Way cool and way fast. Too bad that they might not be legal on the streets or the bike trails. I think they are ok on the wilderness trails and mountains.

Hope this helped!

In one month traveled 5,000 miles on my new 2006 Silver PRIUS. Will need to travel the equivalent of 4 times around the world to get my Ph D. Hope my PRIUS will last that long. Still waiting for Toyota to make the Plug-In or a PRIUS-EV. I already told them I would put money down to be put on the waiting list.

I guess why make something new when they are making a killing off the PRIUS.


Here is the electric conversion kit I used.

http://www.werelectrified.com/unibikekit.html

[EricGo]

Thanks very much, HWS !