Electric Bike Conversion under $600
A couple of years ago, I used to ride my bike (Trek 4500) to school all the time. I have since graduated and commute a longer distance for college. My commute is a long (about 15 miles). It does not have many long or substantial inclines. At most it probably has a few 1/2 mile 6% grades. For the rest, the grade is probably 2-3%.
As you can see, such a long commute would be pretty long and exhausting. It is an urban commute, with lots of cars, traffic lights, and such. Thus, I need to keep up with traffic.
Not long after I started with this commute, I simply resigned to the fact that I need to take the bus. And I did do that, for over a year now. However, the basic problem with the bus is the slowness, unpredictability of arrival, and low frequency.
A cure-all problem would be a car right? Well, I'm a college student, and I can't afford that. So I have decided to reconsider biking again, but electrically.
Sadly, my Trek have been stolen. I currently have a Miyata hybrid bike and a 90's Specialized Rockhopper. I am looking to convert the Rockhopper. The Miyata I will keep for my lightweight biking.
What I want...
I am looking to do a electric bike conversion under $600. I have been digging through the bike forums here, and read up on electric bike conversion.
From what I understand, e-bikekits.com is a good source for conversion kits, and elitepowersolutions.com is a good source for batteries. I want some advice from fellow members that are far more knowledgeable than me. What parts combination would you recommend? From where? It doesn't necessarily have to be from the places I have mentioned.
I just want a conversion that can run well, and doesn't feel too slow, last my entire commute with a couple of miles to spare, is reliable, and won't break down too fast. I am leaning towards a front hub motor. I am fine with other chain, the back, etc, as long as the setup is not too complicated or expensive. The one thing I know, is that SLA batteries are DEFINITELY out of the table. Knowing that my commute is long, it is possible that the battery is drain out by the end of the commute, so high capacity batteries is a must.
As for the fork, I'm not sure if it is Aluminum, but I am definitely replacing it with a new steel fork of some kind.
Currently, the Rockhopper has a setup in the back that there is a dual rack (sides) to carry stuff. I could potentially use area to store the batteries.
If fellow members can give me tips, advice, information, I will be very happy for it. I'm not very literate at all of this e-bike parts. I can somewhat understand, so please take in mind that fact. Reading through the forums, I get a bit confused sometimes due to the word jargle and the fact that I don't know what some components are.
By the way, what is a torque arm and BMS (controller)?
Google didn't come up with anything helpful for either of the two.
Last edited by neoslan; 03-12-10 at 01:47 PM.
I change the cost range to $600 max. I couldn't change the title because the forums wouldn't let me.
Fixed that for ya.
Originally Posted by neoslan
Fixed that for ya.
Originally Posted by neoslan
In the future is possible I will buy this.......... at this moment is impossible for me
1/ebay kit 500w 36v from cammy_cc (ebay) = 230usd shipped
2/tunder sky 20ah batt 36v from thunder-sky.com = 250-300 + shipping
2/headway batt pack 36v 12s1p 12ah = 170+shipping
low than 600usd
I'd probably go with http://hightekbikes.com/kits.html
For the batteries, you got the right idea I think. Buy 36v 20AH THundersky pack from elitepowersolutions.com for about $335 (including shipping)
A BMS is Battery Management System. A lot of battery dealers will tell you that you need one but if you are smart and don't do anything dumb, you don't need one. I don't use one. I did a 19 mile ride just a couple days ago and my batteries are fine. I just don't use more than about 10 - 12 AH . As long as you don't take your batteries over the 90 % capacity limit then you'll be fine. If you buy the 36v20AH lifepo4 from elitepowersolutions.com, just to be safe, I'd do the same and only use about 10 - 12 AH. That way your batteries last a long time and you know you won't over-discharge them. 10AH will get you 20 miles if you pedal. If you have a really efficient motor, it might get you 25 - 30 miles. I have a energy hog motor that likes to use a lot of amps. 10 - 12 AH is still a pretty long ride. You can ride for an hour to hour and a half on that easily.
So I'd buy one of those kits...from hightekbikes or e-bikekit. Then for a charger, I wouldn't buy the one from elitepowersolutions, you'll need a 12v charger or a 36v SLA charger. You might already have a 12v charger for a car battery that you could use. Just make sure it doesn't output more than about 10 amps. I use a black and decker charger to charge mine. It's a bit of a pain to charge 3 packs with a 12v charger because you have to charge each pack individually but I don't mind. It's cheaper. Then I'd buy one of these 3.2v lifepo4 chargers to make sure your cells are balanced. It's $13. http://www.all-battery.com/TenergyLi...rger01300.aspx
You'll want to balance your cells maybe once or twice per month. By balance them, I mean just topping them up to full capacity with the 3.2v lifepo4 charger. I charge mine up with the B&D charger and then I use the 3.2v charger to top each one up. Since the B&D charges to about 98 % , it only takes about 15 - 20 min for the smaller charger to fill the rest of it up.
Anyway, it sounds complicated but it's pretty simple once you do it once or twice. I can charge all my pack up in about 2 or 3 hours if I use a 10 amp charge on the B&D. If you don't want to fool with manually balancing them or charging them, you can get a BMS but that'll be about an extra $100 - $200.
Let me know if you have any questions.
Where did you find a 36v12AH headway for $170 ? I've never even seen a 12AH headway cell. I've only seen 10 AH cells and I think they are about $19 per cell. So a 36v10AH pack would be about $19 x 12 = $228 plus shipping and it's only 10AH capacity. Also, you have to put it all together.
Originally Posted by miquelmah
Btw, Neoslan, buy the Thundersky pack if you want a quality battery pack. Those ebay/cammy packs are crap. I run my bike the whole way full throttle with a 35 amp controller and my battery pack doesn't even get warm.
Last edited by morph999; 03-12-10 at 04:39 PM.
And oh yeah, one more thing....buy one of these
Turnigy watt meter. You'll need it to know how many AH you have used on your trip so you don't over discharge your batteries. Install it on somewhere on your bike so you can periodically look down and see how much battery you have used. It's only $24. It's a must have if you use lifepo4 battery.
That's about it. The BMS basically just prevents you from over discharging your lithium batteries. Lifepo4 can be used to 90 - 95 % of it's capacity but if you use more than that and the voltage of one single cell goes below about 2.5v then that cell is dead and cannot be used again. That's why I say only use about 10 - 12 AH of the 20AH pack so you make sure that you never over discharge it. Using only 50 - 60 % of the pack prolongs the life of them too.
Hi, thanks for the advice.
I took a look at High Tek Bikes and e-bikekit. They both seem to be pretty good companies with support. The prices seem very similar.
Can you advise me on which one is better and which do you recommend?
Does the one from High Tek Bikes support 48v battery packs?
Should I wish to do so, is there a way to get the e-bike to propel me faster than 20 MPH?
The owner of e-bikekit.com says that he quality inspects all his products before he ships them out. The front wheel kit says it can be run at 36v or 48v. From what I've read, the 48v probably will get you anywhere from 25 mph to 28 mph. The 36v will probably get you from 20 - 24 mph...somewhere in that range just so you know. Is 25 - 28 mph fast enough?
The hightekbikes.com only works with 36v. Hightekbikes.com says there motor is 750w and goes 22 mph at 36v. If you wanted to, you could buy a motor from hightekbikes.com and then buy a infineon 48v controller from cycle9.com and put together your own kit to make it 48v or hightekbikes might be able to put together a kit for you that will work for 48v if you e-mail them. He is also on endless-sphere.com by the name of Terry I think. If you make a thread over there, I'm sure he will probably see if it if you give it a day or two. Or e-mail him directly. I don't know him but I know of him.
For $600, you aren't going to get the best of the best but these motors have been tested. I know the Aotema motor from hightekbikes.com has been tested and is of decent quality. I don't know much about the quality of e-bikekit.com but there have been no real complaints on endless-sphere.com yet so it's probably alright. I'd e-mail hightekbikes.com and ask him if he can put together a 48v kit for you with the Aotema motor. The problem is that the 48v20AH thundersky is $416. Is that okay? That's going to push your total kit to about $750 - $800 total if you choose to do that. I like the Aotema motor from hightekbikes.com better than whatever e-bikekit.com is selling (not that it's bad, though) but I'd probably go with the Aotema kit.
Or, what you could do is e-mail hightekbikes.com and tell them that you want a 48v kit with the Aotema motor BUT only buy a 36v 20AH thundersky and then later on, if you want to upgrade, you can buy another 12v20AH THundersky pack and increase your speed without buying another controller.
That way, you won't spend too much but you'll have the option of going faster later without buying any new controller or equipment.
If you do decide to get a 48v kit but use only 36v of battery, make sure the controller will work with 36v because some controllers will not work at 36v because of the Low voltage cutoff.
This controller works at 36v or 48v...I'm not recommending you buy it but I'm just showing you one
I bought a 36v - 72v controller so I can use any voltage from 36v - 72v. It makes things a lot easier. My controller cost $200 though.
Last edited by morph999; 03-12-10 at 08:02 PM.
I think I am going to buy a 36v with a option of upgrade later. That seems to be the better option.
I am looking at the Elite Power Systems website and I am a bit confused.
Whats the difference between these two?
I kind of think that the latter link is a package bundle. What's the difference? Is the former link where I have to buy 3 4-pack batteries and link them together? How would I go about doing that? (Do I need to solder? etc)
If the latter indeed is a package bundle, why is it more expensive than the individual Thundersky batteries?
Thanks for the big help so far!
One is for a package deal which includes a charger. Actually, the links didn't work too well but if I understand you, one is just a package deal and then the other is buying the cells individually. I would recommend just buying 3 of these packs
The only difference is that you don't get the charger. You can get the package deal if you want which includes a charger but my friend who bought the charger said that it sucked so I didn't buy it and instead used a 12v black and decker charger.
The cells come already linked together with copper bars. The only thing you'll need to do is buy 10 gauge wire at a hardware store and some ring terminals and join the 3 packs together. It was really easy to do. I used a pair of pliers to crimp the ring terminals on the wire. If you have a crimper tool, that would be even better. You can find ring terminals at a hardware store or even Radio Shack. What I did was unscrew the bolts, if you look closely on the packs, you'll see that there are bolts that unscrew. I took the bolt with me to a hardware store and found a ring terminal that would fit and then bought some 10 gauge wire and that was pretty much it. Then I duck taped all 3 packs together so they won't move around very much.
Originally Posted by neoslan
Here is a ring terminal
of course I preffer the tundersky batt than the ebay packs............sure......
Originally Posted by morph999
12ah headway............ price 15.6usd+shipping
Thanks so much for your help!
I would have been soo confused without your help.
So let me calculate that...
E-Bike Kit (w/ ship) $386.63
3 4-Pack Thundersky batt w/ ship $342.00
Tenergy Top-off Intelligent Charger w/ ship & tax $22.70
Turnigy Watt Meter $24.00
10 Gauge wire + ring terminal $30.00
Charger $25 (any recommendations on which models to get for optimal performance/charging time?)
It's a little over-budget, but that's fine. I saw on the e-bikekit website an option for SLA wiring for $14. What is that and should I get it? Also, I read that you have a rear wheel setup. How are you liking it? Do you think it is tremendously more difficult? If I like this conversion, this may just be the first of many conversions I do.
I have a front wheel hub motor. Anyway, you'll have to wire it yourself so I wouldn't buy any wire online, I'd but it at a hardware store near you. I went to Lowes or Home Depot and they have these spools of wire and you just tell them how much you want. I told them I wanted 20 ft of 10 gauge wire. It was about $12.
For the charger, I bought a 12v black and decker with 2/10/15 amp selection capability so I can charge at 2 amps or 10 amps. This is good because you have a 20 AH battery so you'll need more than 2 amps sometimes to charge it. Just don't use over about 10 amp to charge.
I would get the one that has a 2/6/10 amp because 6 amp charging is better than 10 amp on the battery. They say 6 amp is the optimal charging current for these 20 AH Thundersky so I'm using a little over it but not by much. Sometimes you'll only use about 4 AH on the battery and then you can use the 2 amp charge. That's what I do. A 12v charger is good because if you upgrade, you can still use that charger. If you buy a 36v charger and then upgrade, you'll still need another charger for that 4th pack.
You can get almost any 12v charger as long as it has an automatic shutoff feature. I'd get this one
Just letting you know that the alligator clips on the end. I had a problem getting them on the bolts because if you look at the battery back, it has a top on it. What I did to resolve this was put on a screw so that the bolts would sit up higher on the battery pack. Just letting you know that if you buy the black and decker charger you might have to do some modifications to get it to work easily. If you get a charger with a smaller alligator clip like the one on the Tenergy charger that you are getting, it might work better. I haven't found a bettery charger so I'm just recommending the black and decker. It'll work but you have to buy some screw to put on the bolts so that they sit higher.
Still, the black and decker would be the best choice because you can use 2/6/10 amps on it. Just keep in mind that you'll have to buy some screws for like $2 to put on the bolts so that they sit higher up so you can get the alligator clips on it. When you go get the ring terminals, just get some screws to go on the bolts. That will solve the problem. But yeah, that's everything you need.
Also, I cut off the ends of the top so I could remove them easily. Here is how it looks...see how the corners are cut off...that's so I can remove the tops easily without taking the wires off...
Last edited by morph999; 03-14-10 at 03:17 AM.
Here is how the cells looks with the top off.. See the copper bars that connect them.
When you take the plastic top off..
See how the alligator clips on the black and decker is a little large, that's why the bolts need to sit up a little higher.
Just make sure that you understand that if you do it this way, without a BMS, you can only use 50 - 60 % of the pack so you don't damage the battery. Just letting you know. You'll still get 20 miles range or more just off 50 - 60 %. It's actually better for the battery to only use that much anyway but I'm just letting you know. If you want to use 90 % of the capacity, you'll need a BMS....like a little circuit board that attaches to the battery. I don't use one but if you wanted to, that's what you would do.
Here is one that you could buy if you were interested. Of course, if you upgraded, you'd have to buy another one. I just don't fool with them because the battery outlasts those flimsy little circuit boards anyway. And people have had problems with them so I just manually balance my packs.
Last edited by morph999; 03-14-10 at 08:42 AM.
żmorph999 this is the photos of the thunder sky 20ah packs of 12v?
thanks for show this........... amazing cells wow
Yep. I just added another 12v on to my battery pack. Now have 48v on it. Not sure if it was the wind or what but I could only get up to 33 mph today. Just took it out very briefly. I was hoping it would go to 35 mph. It could have been the wind I guess. It was blowing kind of hard. The 5303 is supposed to go 35 mph at 48v so that's why I'm a bit disappointed right now. I'll see what it does tomorrow. I guess the pack wasn't fully charged either so maybe that was part of it too.
Originally Posted by miquelmah
I have been thinking, and now I'm wondering this:
Do I have to charge each of the 3 battery packs individually? Or, since it is wired together, it would charge all if I clamp the charger down to one of the batteries.
Also, what's your take on Wilderness Energy kits?