Interested in building an e-bike

General Discussion about electric bicycles.
tostino   10 kW

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Interested in building an e-bike

Post by tostino » Mar 24 2008 11:57pm

I have been kicking around the idea of building an e-bike for quite some time now, and i've been doing some heavy research over the past few days on this forum (best i've been to and why I am asking here) and others.

I would like to start out by saying that I live in Florida, and it is pretty much all flat terrain with virtually no hills at all. I am looking for a better way to go around town, because gas is just getting to be too much, and I would love to have an alternate vehicle that I can use which uses none. At the moment, I don't even own a bicycle, because trying to bike around is impractical for so many reasons in my area, such as distance (for normal daily use it would need to go at a bare minimum, 12-14 miles per charge), and the heat is too bad if you are planning on biking to work without electric assist.

First of all, I would like to state that I have all sorts of tools at my disposal (welder, plasma cutter, etc...), and if any parts need to be fabricated it would be possible. This is all completely new to me, and I really could use some help with all of this.
  • From what i've read over the past few days, it seems like the Dewalt 36 volt battery pack is a good choice for energy storage, but I would like to tear the packs apart and make my own to avoid using the bms that comes with the pack, that limits the current. However, I am very unsure on how to go about that, and what I would need to do about an LVC. I have read all the stickies on the batteries, but I am still unsure. Could someone who has done it explain what is needed? And if there any better options I would like to know.
  • I also need to get some information on charging the battery pack once completed. I've seen a setup with many individual cell chargers wired together (not sure how...) feeding into a pack to charge the cells ensuring each cell is charged to it's maximum potential. I do not know if this is the only way to really go about it, or other options that may be available.
  • Next thing I need is the motor. I have no idea what type of design I want to go with. I don't really like the look of hub based designs, but they seem to be the easiest route. If there are any other paths I could take with the motor that are just as efficient (or more so), please let me know!
  • I'll also need to know what speed controller will be able to be used with what ever motor and battery combo I end up choosing.
I really look forward to getting some feedback, you have no idea how appreciated it would be!

P.S. I would really like to try and keep the price tag under $1,000 USD if at all possible, since part time jobs while going to school aren't all that lucrative.

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lazarus2405   10 kW

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Re: Interested in building an e-bike

Post by lazarus2405 » Mar 25 2008 12:46am

Welcome! We're here to help! So, ask and we shall answer.

First you need to decide how much power you need. This will influence about every other decision, from your motor choice to your battery size to even changing your budget. Power is acceleration, it's hill climbing ability, it's speed. Without too much trouble, you could run anywhere between 1hp and 10hp, depending on the setup. Once you decide what exactly you want to do, and then how much power it will take to do it, then we can tailor the setup to that.

So, how fast do you want to go? So you want to climb the... umm... well I heard there was a hill in Florida. Do you live near it? Do you want to take your bike out for the fun of going fast? Don't be shy about this; Lots commute at 25mph, many ride above 40mph, one rides up to 60mph, and some folks on the fringes dragrace their electric trikes at close to 80mph. Be careful here. Many ebikers find that they enjoy higher power more than they anticipated, and speed is addictive.

Now, your range is very doable. Unless you want to ride at 30, 35mph and higher for those 12-14, you won't have a problem at all getting that range in a $1000 budget. From the start, too, you will want to plan your setup to be able to opportunity charge. That is, if you ride out to a store and want to spend half an hour shopping, wouldn't you want to charge your batteries while you shop? Or eat, or work? Heck, start scoping out unguarded 120v outlets now! :D

The a123 cells, of which the Dewalt packs are made, are perhaps the best batteries out there, but they're expensive, even compared to other lithium batteries. Their primary advantage, though, is that they can deliver ridiculous amounts of current. This goes back to the power question. If you need really high amps from a really small pack, they're your ticket. If you don't need 60A from a 2.3Ah pack, there are less expensive quality alternatives. Search this forum for "Milwaukee" or "E-moli" for an example.

We love hub motors here because they're just so damn simple. Bolt them in, connect wires, and go. They're practically indestructible, have no drivetrain and thus none of the associated noise or energy loss. Using a chain drive system, you can place the motor wherever you want, you can use a lighter motor for the same power output, and you can run the motor in its optimal RPM range at different speeds with different gears. However, there are far, far more things that can go wrong with such a setup. There are many folks here who run chain-drive setups with much success, but they are a small minority. Since you have fabrication skills, you'd have less difficulty with a non-hub setup, but it'll still be a lot more trouble.

The controller won't be a problem after the motor and battery setup are nailed down. Don't worry too much about that.

As for your budget, it's a pretty good one, especially for day-to-day commuting. I have to warn you, though, that you can get a whole lot more power for $1300-$1500.

You'll want to think about what sort of vehicle, too. Cheap-ish full-suspension mountain bikes are generally very good for conversions, and rather popular here. So are adult trikes, and recumbent trikes. You could build your own recumbent of you wanted. If you enjoy building, I highly suggest this route.

So, what are your thoughts on all this? Questions are welcome here. :)

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Re: Interested in building an e-bike

Post by tostino » Mar 25 2008 1:10am

I didn't expect such a thorough reply so quickly! :)

Okay, for the power question, I do not live by Florida's hill, so that is not a concern hahaha... However, speed is something I could use since everything is so far apart by me. I am thinking an average assisted cruising speed of between 25-35 mph (if not a little more...) would be ideal.

Upon further review (thanks google maps) it looks like the range will need to be a little bit higher than I was thinking at first. Just to get down to the town below mine is 14 miles. I am now thinking that a 15-17 mile range is needed for practical use.

I am looking forward to making use of 120v outlets when away from home just as you say, so having a portable, easy to use charging system is something i'm interested in.

The a123 batteries from the Dewalt packs are what I want to use as long as I can stay within a reasonable price range with them, and get decent distance. I really like the sound of them because of their amazing life span, the speed of charging, and the power output they are capable of. However, I am un-sure of my power requirements since I am pretty new to this.

I think I will try my hand at a chain drive system as long as they are able to be competitive with hub mounted motor solutions. Do you know of the best way to go about it? Would the way I described earlier work properly? Or are there much better ways to do it?

I would like to keep my power solution open to upgrades down the road, since I will be saving money in gas, I will easily be able to afford more battery cells at a later date.

And finally, I was thinking about using a mountain bike for the conversion, since not every single road here has room for bikes, or a sidewalk. So for short stretches that are un-paved, a road bike would be useless.

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Re: Interested in building an e-bike

Post by CGameProgrammer » Mar 25 2008 1:54am

Chain drive requires that you create a solid mount for the motor and hook up the gears and things, and it can be complicated if you want a full-suspension bike since the motor has to remain a fixed distance from the wheel. But it sounds like you won't have trouble doing that stuff, particularly for a hard-tail bike (no rear suspension).

Besides ease, the other advantages of hub motors are that they're pretty quiet and they're totally maintenance-free. But they're weaker and less efficient.

For batteries, forget about A123 and stick with lead-acid. They are significantly cheaper than any other chemistry and they come in very large sizes which makes them extremely easy to use. Your range can suffer with them, yeah, but it's not horrible. I used 48V 12Ah with a hub motor, cruising at 35 mph, and had a range of 9-10 miles. They weighed 37 lbs total. You can go with larger batteries for more range, or just go slower. You can always upgrade later, but if you're on a limited budget then lead-acid is what you want.

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Re: Interested in building an e-bike

Post by lazarus2405 » Mar 25 2008 4:06am

First off, let me introduce you to one of the best tools for figuring out your power needs: http://www.kreuzotter.de/english/espeed.htm

This takes wind resistance into account. Put your conditions and speed desired and it'll spit out the power needed "at the wheel". Then, to figure out how much power you need "at the battery", divide this by the motor's efficiency (a good ballpark number would be .85). Then, figure out how long you need to go at that speed and multiply that time in hours to find out how many watt-hours of energy you'll need. Lithium batteries are good for about 90% or their rated capacity, so then divide that number by .9 to find out what watt-hour capacity rating you'll need. To go from watts to amps, divide by the pack voltage if you need the capacity in amp-hours. For example, one Dewalt pack it 33v, 2.3Ah or 76WH.
I think I will try my hand at a chain drive system as long as they are able to be competitive with hub mounted motor solutions. Do you know of the best way to go about it? Would the way I described earlier work properly? Or are there much better ways to do it?
If you want to go for it, then more power to you. Everything is the same as a hub setup except for the motor and the silly bits between the motor shaft and the wheel hub. I'll say, though, that I have never built a chain-drive setup. Though, I can share what I know. The drivetrain will add some noise, but how much will vary. I can't tell you too much about the motor options other than the Etek, which is notorious for being overkill for a bike, as it's a 15hp motor that can draw hundreds of amps (for more information, search for insane-a-cycle, or look here: http://www.electricrider.com/custom/index.htm). Anyway, someone more qualified can help you with motors.

You'll have to work out where to mount your motor. You'd want to decide on a motor first to know its dimensions. You'll need to know its RPM in its most efficient part of its powerband and gear it so that it is around this RPM at your most common cruising speed and so that its maximum rpm correlates to your desired top speed. If you want, you could work out multiple gears and a derailleur system of one sort or another. Just be warned that a bicycle chain won't be strong enough.
...since not every single road here has room for bikes, or a sidewalk.
You mean that you have to go offroad because the roads are not suitable for bikes in some places? If the road, if you could ride on it, would be preferable to riding offroad, just VC it. http://en.wikipedia.org/wiki/Vehicular_cycling The idea is to take the lane and behave as if you were a motor vehicle... which you would be. It's perfectly legal, and usually more legal than riding on sidewalks, let alone safer. Since you'll be able to keep up, you can negotiate traffic just as if you were a little motorcycle. Just remember your hand signals and helmet.
For batteries, forget about A123 and stick with lead-acid.
Well, I'll have to disagree. I'd say get a small a123 pack now and build it out as you go. Still, a123s are very expensive. And SLAs are dirt cheap. However, that is the only way that they are preferable to lithiums. They're heavier, bigger, will only provide ~60% of their rated capacity, perform poorly in cold weather (erm, Florida...), have much shorter lifespans, take longer to charge, require immediate charging after being drained, steadily loose voltage as they drain (while lithiums stay close to their nominal voltage until near the end). SLAs are just a bad investment.

However, if your were to build a trike, or other vehicle that would be more forgiving as far as mounting the large batteries and the weight not hindering its handling, SLAs would be a good choice. You could load them up with a lot of lead and get a whole lot of range on the cheap.

Your budget, though, leaves plenty of room for lithium batteries. Still, a123s are very expensive, but doable. For ~500USD you could get 4 Dewalt 36v (33v 2.3ah) packs for $130 each or 6 Milwaukee 28v (28v, 3ah) packs for $85 each. After the above corrections for motor efficiency and 90% depth of discharge, at 25mph on a mountain bike the Dewalt setup would give you about 14 miles of range while a Dewalt setup would yield about 22 miles. The downside, of course, is that the Milwaukee packs can only discharge at half the C rate and charge at about a quarter the rate. Still, such a pack would be able to discharge at a rate sufficient to throw a mountain bike at 50mph.

I mean, at peak discharge rates, a 66v 4.6ah 30C a123 pack could provide 9100 watts, while an 84v 6ah 15C e-moli pack could "only" provide 7500 watts. (That is, without voltage sag on either, since I don't know what the sag on a123s at that rate are. And correct me if I'm incorrect about the a123 peak rate... thought it was 20 continuous/30 burst, but it might be 30/45).

But I digress. Buy quality lithium cells now, and add more capacity later as your gas savings allows.

A side note: let me explain about the C rate. The C rate equals the fraction of one hour in which a cell can be fully discharged without damaging the cell. A 1C cell can be safely drained in an hour, and a 4C cell can be drained in 15 minutes. To calculate how much current that is, multiply the C rate by the battery's capacity in amp-hours. A 2.3Ah 30C a123 cell could safely provide 69 amps. Two a123 cells in parallel would have a capacity of 4.6ah and this be able to provide twice the current.

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Re: Interested in building an e-bike

Post by tostino » Mar 25 2008 9:36am

I am starting to like the sound of the Milwaukee packs. They offer more storage space per cell for a cheaper price than the Dewalt pack. Is the charging C rate really going to be a problem? The biggest charger I could find for this type of battery (at a reasonable price) was 2A. At that rate, it wouldn't make a difference if I had the Dewalt or Milwaukee, both would be limited by the charger, right?

I honestly doubt I will need the higher discharge C rate of the Dewalt cells. If I want to go fast, I have my dirt bike. It will smoke any electric bike I can build any day. I am really just trying to create something that will allow me to travel from place to place in a quick enough manner, with enough range to not leave me peddling home.

After using that energy calculator, it looks like I will want to keep my average speed around 22 mph. I do however, want to be able to go in the 30mph range when necessary, just not all the time. For an average 15 mile trip, it would take 570 watts traveling at 32mph, where that same trip would take 372 watts while going 22mph.


And for going on the road, there are very few roads with speed limits less than 45mph, while quite a few are 55mph+. Not to mention I live by US19. It is one of, if not the most deadly roads in the country. I'll take my chances on the sidewalk or side of the road for the stretches without sidewalk. I'm serious, i'd be splattered all over the road in no time if I tried driving there...


Do you have much information on the Milwaukee cells? Would they need pretty much the same stuff as the Dewalts? Not that I know exactly how to set up either of those cells anyways.

Your help is sooooo appreciated, thanks for taking the time to talk with me so far :).

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Re: Interested in building an e-bike

Post by lazarus2405 » Mar 25 2008 5:24pm

If I want to go fast, I have my dirt bike. It will smoke any electric bike I can build any day.
...are you sure? You'd be surprised. Unless it has 20+hp, you can build an electric that will smoke it. Especially at low speeds or drag race sort of conditions, since the electric motor can go from a dead stop to full torque instantaneously.
I am starting to like the sound of the Milwaukee packs. They offer more storage space per cell for a cheaper price than the Dewalt pack.
Exactly why I love them.

For charging, the best solution in my opinion is to charge Milwaukee packs with Milwaukee chargers. They just slide on the packs and completely charge and balance them in ~50min. For my build, I bought 3 chargers with my 6 packs, so I can fully charge in a little under 2 hours. Since this is how these packs were built to be charged, you have to almost nothing to wire. The only thing really advisable is to open up the packs and connect wires for discharging (that is, bypass the BMS). Then, use the BMS for charging.

Any question you could possibly have about the Milwaukee cells I'll be happy to answer. In fact, I need to stop typing to rewire my packs! (I wanted to make everything more compact, so I'm removing the batteries and chargers from their cases and wiring them more closely together.)

I haven't made a build thread you can look at, but I can link the thread of mine from when I was in your position. http://endless-sphere.com/forums/viewto ... 3&start=20

Hope it helps.

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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 12:15am

...are you sure? You'd be surprised. Unless it has 20+hp, you can build an electric that will smoke it. Especially at low speeds or drag race sort of conditions, since the electric motor can go from a dead stop to full torque instantaneously.
Yup, it's a 40hp crf250. 0-65 (top speed limited by gearing) in about 5 seconds.

Okay, so now to the Milwaukee packs... I would be so happy if I didn't have to tear em all up. However, I am worried about disconnecting the BMS when running, what if I run them down? From what i've read, that is the only thing that will really kill the cells. Is there any safety net I can put in place to try and stop blowing them up?

Also, from your experience, would it be possible to install a switch on the pack that would connect/disconnect the BMS without having to open the pack up?

Lastly, Milwaukee has two different chargers available, one that says it's only for the 28v (more expensive) and another that is a 18/28v charger (cheaper). Is there any difference between the two of these that you are aware of? If so, what is it? lol

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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 2:39am

Okay, i've got a few of the needed parts together. I'll post the list here, and will need some help finding the remaining parts.
I still need a motor that will work with the speed controller, and I would like to find a freewheel crank conversion, as that seems to be a better way to go about the power transfer now that I think about it.

If I am missing anything else, let me know! :)

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Re: Interested in building an e-bike

Post by lazarus2405 » Mar 26 2008 7:07am

Some thoughts:

I highly suggest the Schwinn S-series of Target bikes. I got mine used, an S-25, and it's almost perfect for electric conversion. Full suspension, full front triangle for batteries, strong aluminum frame, really beefy rear dropouts (very important for hubs, since all the torque is at the axle), etc. The S-40 is the same deal, except with a disc brake in front. http://www.target.com/Men%E2%80%99s-40- ... rh=&page=1

Though, that will make mounting the motor slightly tricky, with a rear suspension. Far from impossible, though. If you use a freewheel crank and run the motor through the front gears, you'll be fine. If you use that as the drivetrain, though, you might find the bike chain to be too weak. Of course, that depends on a good many things.

More importantly, scratch off that controller from your list. Either it will die on you because of low-grade FETs or insufficient capacitors, or it will make your bike feel like an electric wheelchair while accelerating. Do not pick a motor to work with a specific controller, but pick a motor that fits your needs and then find a controller to power it. So find your motor first, then get a quality controller that exceeds the ratings of the motor. Unfortunately, someone else will have to lend a hand there. Stupid non-hub (i.e. real) motors. :-p

Also, the freewheel crank is an excellent idea. You could mount the motor somewhere near the crank chain onto the front sprocket to use as a reduction gear. Then, you'd still have 7 gears in the rear derailleur for your shifting pleasure.

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Re: Interested in building an e-bike

Post by Malcolm » Mar 26 2008 9:03am

Like lazarus says, I'd wait until you know which motor you want before picking a controller.

I've just finished building a freewheeling crank drive myself and I've got to say I'm really pleased with it even though I've just used a basic brushed 250W motor (my1018z). Accelerating through the gears is great fun, and it'll buzz along happily at 24 mph on the flat. Disadvantages: it's noisy, although that doesn't bother me personally, and it takes a fair bit of tinkering to get it set up just right. You have to make sure you get the chain line spot on and you've got to make sure the motor is mounted rigidly. My first motor mount bent like a piece of spaghetti the first time I opened the throttle.

To get the sort of speeds you're after you'll need at least a 500W motor. Have you looked at these?
http://www.elationebikes.com.au/
http://www.cyclone-tw.com/
http://www.bike-elektro-antrieb.ch/

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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 1:04pm

Thanks for the advice on a bike, i'll take a look at it :D.

However, from what I read here, the controller seems to surprisingly be pretty high quality, with the ability to be easily upgraded to handle much higher voltage and amperage.

Secondly, where can I buy the parts I will need for a freewheel crank conversion? It's good to know you like it so far.

I was wanting a 500-600 watt motor, however the only ones I could find were 24v, and I was wanting to go with a 48v setup (2s3p on the milwaukee packs). Would those 24v motors just blow up? The only 48v I could find was a 1000+ watt, and that isn't something I am interested in quite yet :p...

Any other ideas for a 500-600 watt 48v motor?

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Re: Interested in building an e-bike

Post by CGameProgrammer » Mar 26 2008 1:14pm

You're confusing electric motors with internal-combustion engines. In an EV, the batteries are the primary source of power, not the motor. The wattage of a motor merely specifies the maximum power it's rated to handle. You can go higher than this but it'll likely overheat. Small motors have lower rated maximum power than larger motors.

I'm simplifying a bit but that's roughly how it is. 2000 watts is about enough power, with a hub motor at least, to cruise at 34-36 mph on level ground. 500 watts is about enough power to cruise at 15-20 mph. You'd probably get somewhat better results with a chain setup.

By the way, you can't determine what voltage you need until you choose a motor. Hub motors tend to be high-voltage and low-current. "Regular" motors like you're considering using tend to be lower-voltage but high-current. Choose the battery configuration that best suits the motor.

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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 1:58pm

I understand that the batteries are what is going to give an electric motor it's power, however, I do not quite understand what would happen if I were to run a lower rated voltage motor, and run it at higher. Would it just burn out quickly, would the RPM go way up, or would it just possess more torque?

Anyways, what are your thoughts on this motor: http://www.thesuperkids.com/600wabmchsps.html

Or possibly even this one: http://www.thesuperkids.com/450wahitocue.html

I know that an electric motor can use MUCH higher than it's rated wattage for short periods of time from what i've read on this forum, I just don't know exactly how bad it is for the motor.

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Re: Interested in building an e-bike

Post by fechter » Mar 26 2008 3:19pm

The BMC 600w motor with external controller is what I use on my Vego. It will run great at 48v. I've run up to 60v, 100A peak on mine with forced-air cooling. It can handle around 1.5kw without forced air.

Increasing the voltage makes the motor go faster. Increasing the amps gives it more torque. The limiting factor is usually heating, which increases with amps, not volts. There are limits, though. If you overvolt too much, the efficiency will drop to an unacceptable level or the motor could fly apart.

The one shown in the URL above probably has the built-in controller and will not work above 24v. Even at 24v, they had a tendency to blow the controller. You need to specify one made for an external controller. Either way, you'd need a lot of reduction to drive a bottom bracket with one of those. A single reduction will not be enough. Some versions of the Currie USPD planetary reduction will fit that motor.

The Kollmorgen motors are frequently around for $20 or so. They are smaller and won't make as much power, but still decent motors up to around 600w. They are the same diameter, but thinner.
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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 5:27pm

Fechter, would that BMC motor I linked to be the one I want? If not, where could I find the right one? I actually don't know if it's even brushless...
If it is brushless, would it work with the controller I wish to use? If not, what controllers would be compadible?
Grr these people need to provide more info on their websites! Well thank you for any information you may have :D.

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Re: Interested in building an e-bike

Post by tostino » Mar 26 2008 11:16pm

Ohh I found what you were talking about!!!

link: http://powerpackmotors.com/POWERPACKMOT ... opage.html

I am unsure if you are acquainted with the controller I selected, but I want to know if it should work with this motor or not.
link to controller: http://cgi.ebay.com/48V-600W-brushless- ... dZViewItem

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Re: Interested in building an e-bike

Post by lazarus2405 » Mar 27 2008 4:19am

Well, that motor looks like the right fit. Also, after reading up on the controller, I think it'd be perfect. From the information in that thread, I'm really actually impressed. The caps are rated at 63v, it uses 12 fets, and the ones it uses are rated for 75v 9.5mOhm 80 amps continuous. That thing really is overbuilt!

Fechter, how difficult is a forced air cooling mod on this motor? I mean, using a 56v pack and some improved cooling, this setup should be able to run 40amps with a little solder on the shunt, correct? That'd make a rather nice setup.

So, I say run that controller with that motor and those batteries. You'll have to configure the 6 packs in 2s3p 56v 9ah. That's no big deal; it actually simplifies a couple of things. If you were to run 3s, you would have to crack open the battery and bypass the BMS for discharging. With only two in series, you can leave the things completely intact. You can use female spade connectors to attach the packs to each other and then to the controller. Then, to charge them, simply remove the jumper wires between the batteries and slide them on their chargers. Very elegant.

Have you seen jondoh's build with these batteries? Check it out, including the video, here: http://endless-sphere.com/forums/viewtopic.php?t=233

So it looks like all that's left is the reduction gearing, right? If the bike chain can handle it, and I have no idea whether it can, you could reduce it like fechter said and then run it through the bottom bracket. I'd say that 40mph would be a good top speed. Calculate the reduction so that you reach that top speed with an 11-tooth rear sprocket and thus 15mph with a 28t rear sprocket. Then - again assuming the bike chain can handle it - you can start in the slowest gear and accelerate through them till you reach your desired cruising speed. When you get to your desired cruising speed, you should be at full throttle in the lowest gear you have that will give you the speed. The goal is to keep the motor's RPM as close to its maximum (unloaded) speed for a given voltage, which will be the motor's peak efficiency range. This use of gearing to keep the motor's RPMs high at different speeds and thus greater efficiency is the real advantage of a non-hub setup.

...

It also is what gives Safe naughty dreams at night.

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Re: Interested in building an e-bike

Post by fechter » Mar 27 2008 9:25am

tostino wrote:Ohh I found what you were talking about!!!

link: http://powerpackmotors.com/POWERPACKMOT ... opage.html

I am unsure if you are acquainted with the controller I selected, but I want to know if it should work with this motor or not.
link to controller: http://cgi.ebay.com/48V-600W-brushless- ... dZViewItem
That's the right motor.
The controller should work fine after you figure out the wiring.

9.5mohm and 80 amps continuous is NOT really overbuilt, in fact it could blow quite easily if you increase the current limit. If you upgrade the FETs and caps, it should be just about like a Crystalyte.

The cooling setup I used is about as easy as it gets. I usually run around 20-30 amps crusing at 27mph. On a steep hill, it goes up to about 60 amps.
"One test is worth a thousand opinions"

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Re: Interested in building an e-bike

Post by tostino » Apr 02 2008 10:46pm

Just wanted to update ya all, I picked up a Schwinn S-60 DSX at Target today for $250. I've been riding it around for a couple hours now, and like it a lot. I'll be ordering my motor, ESC, and throttle tonight, and will keep you all updated on my progress. Pictures of the new bike will come in the morning.

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Re: Interested in building an e-bike

Post by tostino » Apr 03 2008 6:51pm

Here are the pictures of the bike I picked up! I got all the parts other than my batteries ordered, all the extras needed i'll just pick up at local bike shops or hardware stores.
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lazarus2405   10 kW

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Re: Interested in building an e-bike

Post by lazarus2405 » Apr 03 2008 6:59pm

So what are you going to do about that seat there, eh?

tostino   10 kW

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Re: Interested in building an e-bike

Post by tostino » Apr 03 2008 6:59pm

What do ya mean?

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lazarus2405   10 kW

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Re: Interested in building an e-bike

Post by lazarus2405 » Apr 03 2008 7:08pm

Have you sat on it yet? Ridden on it?

You'll want the biggest, cushiest seat you can find for commuting.

tostino   10 kW

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Re: Interested in building an e-bike

Post by tostino » Apr 03 2008 7:13pm

Oh oh oh, lol yeah, that can be changed later. All I care about now is getting it working, after that I can fine tune it to my liking.

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