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E-bike E-xperiences?
Jakedata writes "I am in the process of building my first e-bike. I intend to use it to commute to work a couple times a week, weather permitting. I can only assume that many members of the /. crowd are already riding e-bikes and would be only too happy to share their experiences. I am looking at a very affordable e-bike conversion kit from Golden Island Machinery. They offer a 36 volt lead-acid battery pack for it, but I am concerned that it will be too heavy. Rabbit tool has a selection of components and power options but they are pretty pricy. So, is Golden Motor's kit any good? Is lead acid OK to start off with? Does someone want to donate a direct-conversion methanol fuel cell to the project?"
If it were me, I'd dump the lead-acid cells and use Li-Poly (Lithium Polymer).
Sure they're more expensive but they're much, much lighter due to their greater power density (hence a lot easier to pedal when you're not using the batteries).
Just make sure you use a real Li-Poly charger otherwise they could go bang.
I'm not sure why on the fuel cell, but from racing I can tell you a few things.
You can't (not as a fuel) buy ethanol, you can buy e-95 (95% ethanol, 5% methanol) Drinking ethanol (100% ethanol) is strictly taxed. They use e-80 and the like a lot in brazil instead of fossel-fuels. e-95 got a bad name as of late becouse it can be used in explosives with ease. Methanol works better as a fuel becouse it absorbs less water from the air (but is still really bad about it) and its cheaper. Also, it smells really good when its burning, but if you drink it, it will pickle your liver. In world war II the us used methonal in torpeados, some people still call it torpeado juice. Also methanol has a higher octain rating (really high, like 130 or something like that) and it can cool your manifold better then gas.
!
If you can shower at work, it's easier, but it's also very possible to take it a little easy on the way in to work and not show up smelling. Then you get the option of hammering it on the way home or just taking it easy. :)
Good luck with whichever way you decide to get to work -- far better than hauling a 3000lb steel beast to and fro every day!
After getting into BattleBots years ago, I decided to reduce my commute to college (before I graduated) by building an electric scooter out of "spare" parts. It's not an e-bike from the standpoint that I didn't want to have to input any energy into the system myself (i.e. the motors had to do all the work). For cost and simplicity reasons, I chose to go with SLA (sealed lead acid) batteries and a couple of overvolted motors. With the proper timing, I achieved a flat speed of 16.5 MPH on two 1HP motors. With 64Ah (@12V) of Pb-acid chemistry onboard (this weighed a whopping 50 pounds), I had a maximum range (tested on all terrain including large hills) of just over 12 miles.
:-)
That's what I did and perhaps you can learn from what I would have done differently. First off, I would have used NiMh batteries. This would have cut the weight in more than half and also would have allowed me to customize the pack more both in shape and capacity (I only needed to go 9 miles in a day). The only downside to this was the charge time. SLA batteries are pretty indestructible and I could charge the full 64Ah in around an hour. With NiMh, you're talking about several hours or less if you don't mind compromising lifespan (with the right charger you could charge the same capacity in NiMh in the same time if you didn't mind getting only ~100 charges out of your packs). If I had the cash, I would probably use the high capacity, high discharge Li-Ion batteries from PowerStream (http://www.powerstream.com/LL.htm) as they would be incredibly light (~10 pounds for the same capacity).
As far as the motors went, I was fairly satisfied with the power output, but would have liked more. If you compare it to a car (~100HP for ~2000 pounds), you should have ~10-15HP available for the same performance. Now with electric motors, due to their differing torque curves (in comparison to internal combustion engines), you can achieve similar results from significantly less overall horsepower, but I still would have preferred having 3-6HP on my project.
Of course, if you go with high output motors, you need a speed controller capable of handling the current. And if you go with the Li-Ion batts, you need a fairly expensive charger.
You can take a look at some basic pics of my scooter at:
http://sloviper.com/hobbies/scooter/index.html
A good place for parts is:
http://www.robotmarketplace.com/
Cheap Ni-Mh batteries can be found at:
http://www.batteryspace.com/
I have used them in BattleBots before and they hold up decently, almost as well as the "expensive" ones from http://www.battlepack.com/
If you have any specific questions, feel free to contact me. I love discussing this sort of thing and have had tons of experience.
In theory, theory always works in practice. In practice, theory rarely works. <><
I cycle 10 miles to work some days. This isn't actually too bad a problem, provided:
1. You allow yourself enough time. If you don't have to rush, you won't sweat very much on a ride of that length. I like to leave myself an hour so I can take it nice & easy.
2. You live in a relatively flat area. I wouldn't want to do it if the office was halfway up the side of a mountain, for instance...
3. You pack aerosol deodorant and a change of clothes. This will remove the worst of your sweat problems.
...there are already dozens of comments saying "Why don't you peddle your bike to work you lazy bastard".
It's PEDAL, not peddle! Peddling is marketing. Pedaling is using your feet on the pedals of a bicycle.
Oolite: Elite-like game. For Mac, Linux and Windows
On my no so great MTB, I average about 28km/h (no wind) over 2 hours (no stopping). You can't go much faster on a MTB over long period of time without help from the weather.
Short distances, like <5km, you can push to 45+km/h on MTB:)
Hi, I would avoid trying to deal with Golden Island Motor directly for ordering a single conversion kit, they don't do the english/communicating thing very well and the cost to wire transfer and ship just one hub motor will exceed the listed kit price considerably. You can get very similar value hub motors that are distributed locally through http://www.wildernessenergy.com/ and http://www.evsolutions.net/, a supplier of the http://www.crystalyte.com/. These are all direct drive motors, no gears to wear out and perfectly silent, but also fairly heavy for their power output.
I've also ordered reasonably cheap hub motors from http://www.elebike.com.tw/. They have an interesting selection including some internally geared models, and are quick to respond to queries.
Good Batteries continue to be the biggest hurdle for DIY e-bike experimenters because even though there are tons of asian companies that reportedly make them for cheap, there are simply no local suppliers. If you don't mind trying to import from China, some companies to check out:
1 http://www.peacebay.com/,
2 http://http//www.hyperbattery.com,
3 http://splendidbattery.com/,
4 http://www.gmbattery.com/,
5 http://www.thunder-sky.com/en/index.htm
Personally haven't ordered from 1 or 2 yet, 3 has very reasonably priced lithium polymer ($.82/watt-hour) and NiMH ($.40/w-hr) packs and will sell in individual qunatities. My favorite so far are the prismatic NiMH packs from 4, GMBattery, because you can access each individual cell and restack them easily. Finally there is the infamous thundersky who have lithium-ion batteries for less than most companies' NiMH. Their old 10Ah 36V setup had no protection circuitry and a few problems, but their new 20Ah 36V ebike pack looks a bit more reputable. Note that the 24V 4Ah NiMH packs from batteryspace.com that someone recomended are GARBAGE. Ours turned out to have only 2.6 Ah capacity and couldn't deliver more than about 5 amps. If you buy from batteryspace, be sure to get the 30Amp high rate pack.
Lead acid isn't really that bad if you're generally doing ~20km ish trips so you can get away with lower capacity pack. NiMH has about twice the energy density, and Lithium packs are 2-3 times better than NiMH.
I see a lot of people here have misconceptions about ebikes and exercise. I find I pedal as hard or harder riding an assisted bicycle than a regular bike. The difference is that I move at 42km/hr instead of 26, I don't slow down on the hills, and no matter how hard I work I don't get sweaty because the breeze at those speeds is so strong. This is a much overlooked fact of ebiking, the wind keeps you cool and dry.
Justin Lemire-ElmoreMost people significantly overestimate the steepness of hills, often by 3-6 times.
What you percieve as "30 degrees" was probably 5 or maybe 10 degrees at worst.
Most councils restrict roads to an incline of about 10 degrees maximum!
(google for "overestimate hills")
I'm a perfectionist but I'm trying to cut back.
On top of that, I find cycling a lot less stressful than driving, it's relaxing really
Cycling is relaxing, but only if you're doing it where there are no idiot drivers anywhere near you.
I spent a year cycling the 45-minutes to work, unfortunately I don't now as I work much to far away from home to even consider cycling. When I was cycling, and even now when I cycle, not a journey went by without some idiot driving to close, pulling out in front of me or doing something completely idiotic within a few metres of me, putting my life in danger.
The main reason I cycled was because I had no other means of transportation, I mean there was the bus, but it was often full and therefore wouldn't stop for you, the cost adds up paying for it everyday, and the majority of the time it was quicker and easier to cycle, although it was good to know I had the option if I couldn't cycle for whatever reason.
I don't know about any other country, but here in the UK you are required by law to leave at least six foot between your car and any cyclist you're overtaking, that is the approximately the space that a cyclist would need if they fell off their bike into the road. I'm sure that 99% of the drivers are completely unaware of this.
Everyone wonders why more people don't cycle and I think one of the main reasons is that it is outright dangerous. Until there are more cycle routes that don't use roads, or drivers are more considerate towards cyclists, I don't think any more people will cycle to work.
My solution to the passing problem is to be bold and ride in the middle of the lane, especially if there are two lanes.
According to the highway traffic act here in Ontario (and I think all of Canada) a bike is "vehicle" and thus the lane is mine.
I got into shouting matches about this with drivers, to a point where a cop was interested and told the guy if he doesn't shut up and move on he'll gonna ticket him for dangerous driving (he saw how the guy almost ran me off the road).
Why do I take a whole lane? Because that way I have at least some "escape" room if need be.
Interestingly enough, a lot of guys I know down in the states always tell me that they "ride on the shoulder" wherever they can or "squeese to the right" as to not be "hindering" the car traffic.
Personally I give a shit about this, If I am already squeezing on the side they sure as hell won't respect me when passing, and most of the time people go the wide way around me, if they can't do it safely, then I guess they shouldn't pass at all.
[rant off]
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So, I have a y-frame MTB with a suspension - I'd rather waste some of my output (about 12%, BTW, not 20-30%) in absorbing the back-trail type of terrain and saving my back (rear shock). The front shocks are worth it because I can maintain a higher average speed over rough terrain, as the shocks help keep the tire on the trail.
While I agree that a lot of people buy MTB-style bikes for how they look (or because they don't know any better), one can't automatically assume that every city-rider who has an MTB is clueless. Especially when not everyone can afford multiple bikes -- I know people who commute on city streets, but buy the MTB because they off-road on weekends and don't want to own two bikes.
We may not imagine how our lives could be more frustrating and complex—but Congress can. – Cullen Hightower
So when its a biker who isn't hugging the curb, but instead taking up an entire lane, I reserve the right to get pissed.
I hope your license is taken away from you before you kill someone.
When you are driving any car, you are operating machinery that has more lethal potential and more difficult to control than any modern firearm. It is dangerous to give firearms to people who get pissed easily; people who cannot control their emotions are even more dangerous in a motor vehicle. They account for a big portion of the highway death toll in the USA, since the state of being pissed is a very accident prone state. You should not be driving when you are pissed. There are anger control clinics available-- you should take advantage of one of them.
In all the states where I have bicycled, it is legal for a bicyclist to "claim the lane"-- and the law requires him to do so when it is unsafe to do otherwise. A bicyclist in the middle of a narrow lane is safer than one who hugs the shoulder because he is more visible, because he causes other traffic to slow down to a speed that is safe for the current conditions, and because he is not encouraging drivers who maybe are poor at safety assessments to attempt to pass without changing lanes.
Good bicyclists minimize this practice through route planning and being courteous in using turnout opportunities when those are safely available. That does not mean weaving in and out of parked cars-- which is a dangerous habit.
Bicyclists are another slow moving vehicle, like farm equipment, metermaid threewheelers, and drivers rubbernecking for an address. Of course you probably get pissed at these other legal users of the road, too. Get some anger management before you end up carrying a sack of guilt around.