Re: Lets get technical
Ok so far so good but don't stop there. How does this relate to running a motor bicycle? How many battery's is it going to take to go say, 25 mph for even a modest distance like 25 miles? How much will the battery's weigh? How much will they cost? What about physical size?
In other words, it they're so good why aren't motor bicycles running around using them?
Great discussion here! Glad to see that we can all talk together and not get too hot under the collar (ok, maybe a little heated, that just makes it fun!
I'm brand new to this site, I have been doing the E-Bike thing for the better part of a 1 1/2 year, and I want to show you what I have been able to do with VERY limited electrical knowledge and a TON of reading, posting and asking questions on Endless Sphere.
First off, now that ES is back up, I can show you a lot of the info I am about to pass on first off, let me say that in the beginning I was trying to decide on either gas or electric, and choose electric mainly because it's more acceptable and will not cause you a hassle where I live using it on the street & bike paths (here in Oregon, as long as it is under 1000 Watts, goes 20 MPH max with no pedaling, it's treated as a bicycle, however, with electric you can get away with tons more power with out raising an eyebrow!)
My father was in a serious bicycle accident, got a pretty nasty knock on the head, and needed something to help him back on the bike, so we got into electrics.
First we did the cheap "Lead Sled" version with 3 car batteries we had laying around in the yard and I was really disappointed with the "only 15 MPH" performance of the bike until I measured the weight of the old kiddy trailer we had those batteries in, and it weighed 115lbs!!?!
Once we got smaller lead acids (SLA's) from a cheap used battery + the 2 little bitty ones from my nephew's razor pocket bike, we had something worth riding, and it was going about 22-24 MPH on the flat, no pedaling, and this was with a cheapo dept. store schwinn I bought for $20 at a yard sale, so all told we had, $330 shipped into the Amped Bikes Direct Drive (no gears in the hub) hub motor. The bike weighed about 80lbs though!!!
The range realistically was more like 15 miles, but hey, we did it with a $20 used SLA from the battery factory, a $20 yardsale bike and kit.
Total: $370
Now, fast forward, I have used a geared hub motor kit that was pretty light, but didn't have the power I wanted, I had been using 36V and 28V Dewalt battery packs with a special interface card that fooled the battery pack into thinking it was plugged into a drill while it was powering my bike.
So, I was using $800+ worth of batteries (56V) and charger on a 36V Amped Bikes rear geared hub, on a Nishiki MTB I bought cheap at the local pawn shop. I was pretty happy with the lighter weight than the DD hub motor we had on dad's bike (mine was 9lbs his is 13lbs) but still, it wasn't super light, I think it was around 75lbs and would take me to my brother's house 27 Miles away with MAJOR hills (some up to 12%) in-between.
I could do all of this on about 30 - 40% of a charge, and it took around 3 hours to recharge the batteries (I had eight 28V Dewalt batteries ran 2 series, 4 parallel to make a 56V 9.2 AH battery) and my battery pack weighed about 16lbs. I was pretty happy with this, and could get a good 26 - 27 MPH on the flat, but was shocked when I tried it on a hill, and although it would do it, it wasn't geared for anything but speed, so it sacrificed torque.
I was then surprised even further that the gearing of the planetary transmission in the geared hub was limiting the performance so much that when I used this same 56V battery on my dad's motor (we decided to try switching) the same motor that I thought was more of a dog (he was running 36V Dewalt batteries but wouldn't get enough of them to make it worth it, i.e. he was trying to use way too little capacity, so he had no torque and went back to his SLA's lol!) at 36V and now I ran it at 56V and it was a rocket!
If you want a super easy plug & play set-up, use some of the batteries that Thud suggested, and get a 9C (nine continents) Direct Drive hub motor on the back wheel in the 9 X 7 winding, and depending on how fast you want to go, just add volts. With 56V of Lithium Iron Phosphate (LiFeP04) batterys like the dewalts use, that same "dog" would fly up the local 8% grade hill (no pedal start just throttle and go) at 12MPH and this was amazing compared to my geared motor that needed help and would only creep up it at 7 - 8 MPH (this is a place where I can only pedal 3- 4 MPH alone)
Now I know what you are thinking " Yep, I knew the electrics were heavy and underpowered ... "
Hold on, fast forward again today to my LATEST E-Bike build, enter The EBoo.st (Kepler Drive)
Here is a video from the inventor:
YouTube - Kepler_Drive_on_New_Inventers.wmv
On that video, you will hear from an Australian who took a bunch of good ideas that were already out there and put them together in a unique way.
The real question for any motorized bike IMHO is it going to be a pedal assisted bicycle, or a ultralight motorcycle?
I like both! Don't get me wrong, but for the most part, I am concentrating on the pedal assist, as I have Gulf War Syndrome, and bicycling is about the only thing that helps my symptoms, and with out an assist, I would get stranded from time to time when my chronic fatigue nearly has me bed ridden.
Here is my build:
Endless-sphere.com • View topic - Kepler Drives are HERE!!
It's 41 lbs (15 lbs for motor, battery(I have 18AH's 3x the nominal battery) & accessories, another 2 lbs for my gadgets and gizmos, the bike started at 24 lbs) and so far, while I am still being extra kind to the batteries as I break them in for the first 10 charging cycles, I have only gone about 50 miles using 2/3 of the total battery capacity.
This is with the same new Lithium Cobalt (commonly referred to as just Turnigy Nano Tech) that Thud was describing, that is also being used in the Chevy Volt and Nissan Leaf, and to give an example, another ES's member, used just a 3S (10V) pack of the 45 - 90C variety to turn over his father's high compression v8 Work truck!!
Here's the thread, first he started by starting up his turbo car multiple times, then he moved up the the big block high compression V8:
Endless-sphere.com • View topic - Nano-tech LiPo demonstration Engine cranking
I am using the "less powerful" 25 - 45C version but only 4S (15V) because my first plan was to use a different motor and voltage (8S or 30V made up of two 4S batteries in series, paralleled 3 times, making 30V, 18AH's) and to my amazement, at only 15V (I am using less voltage than anyone else I have seen on ES) I am getting 22 MPH solid even in the rain with a stiff headwind, on a bike that feels no heavier than any average department store bike!
I don't really have a "dog in the fight" I like both gas and electric, electric is what I know best so far, but I see reasons to use both.
If you're curious about what electrics are capable of, check out Dr. Bass's absolutely INSANE 67MPH Down Hill Bike with 3in tires! (Ok, ok it's really a motorcycle with pedals!
Endless-sphere.com • View topic - Doc's Giant DH comp 2003 Project !
Bottom line, I think it's really about personal choice, some people like the quiet of an electric, some like the ease of filling up at a gas station with an ICE.
I will have both, but first I am going to take my E-Bike coast to coast to show people not only can it be done, but how easy and simple it is.
It takes about 1-2 hrs to charge up my batteries, but this is only because I am being extra cautious, charging them individually instead of in series as I too have seen all the youtube vids of exploding LiPos.
I had a couple donated to me by the local hobby shop, I did some experimenting of my own and tried to get a LiPo battery to go boom, but it wouldn't even fizzle, not even after I shot holes all the way through it with a high-powered pellet rifle and dunked it in water.
I could easily charge my entire pack in 1 hour or less, and when I go on my tour this spring, I will be using double that capacity (36AH's shooting for 80 miles range between charging regardless of the conditions) and I will be using solar for some of my needs, however, to really make it feasible I will be plugging in at various places along the route from West to East coast, mostly at restaurant, camp grounds, coffee shops or any friendly touring bicyclist's house where I will be staying for most of the trip for lodging.
The next build I make will be the same motor in a 7 to 1 single stage reduction #25 chain drive on the same or slightly higher voltage to keep things light. I will be geared for 31 MPH no-load speed, but in practice I expect to get closer to 25 MPH on the flat, and hopefully 16 - 20 MPH up-hill on a 10% grade with me & my fully loaded touring E-Bike coming to about 350 lbs.
I have had the bike in the first friction drive build loaded up to 110 lbs (bike not including rider, 180lb rider = 290lbs) and to my amazement it pulled up 12% grades at 8 - 10 MPH! This was before I had the proper alignment of the roller, and was loosing a lot of speed to poor grip of the friction drive, now I have gained considerable grip and hills that I could only hit at 10 - 12 MPH with out cargo, I can now do at 16 MPH with moderate pedaling, and this is with a friction drive! With the chain drive I expect considerably better performance.
