Step 10: Balance of System

Balance of System is a fancy term that refers to "and everything else".

In an electric vehicle, you already know about the main components, like the motor and batteries, but it can sometimes be the little things that people don't talk about, and can be the most confusing.

In this case, we will talk about the on/off key, main fuse, contactor, battery disconnect key, pre-charge resistor, shunt and ammeter, instrumentation, power indicator light, and DC/DC converter. Most of these components are shown right on the wiring diagram, along with their specs.

On/Off Key
When I got my cycle frame, the ignition key was broken. I replaced it with a simple keyed electrical switch. It's a "double-pole, double-throw" switch, which means that it completes two separate circuits at the same time. That's great, because with one switch, I can turn on both the 12V accessory system and the 48V drive system at the same time.
I built a mounting bracket by cutting down a piece of metal from a recycled computer case. I drilled a hole to mount the key switch, two holes for bolts to mount the bracket to the cycle frame, and painted it black. The switch gets two sets of wires to the back of it, both with small crimp-on ring terminals. One set goes to the DC/DC converter to run the 12V accessory system, and the other pair activates the main contactor for the 48V drive system.

On a motorcycle that has an existing, working ignition key, you can route 12V power from the key to activate a relay that will turn on the main contactor and motor controller.

Battery Disconnect
The battery disconnect is just a big kill switch. It completely disconnects the batteries from the rest of the system. It's an easy way to disconnect power for when you are working on the cycle, and acts as an emergency backup in case the main contactor ever failed. Both the On/Off Key and the Battery Disconnect are mounted on the left side of the motorcycle, not far from where the "Emergency Reserve" switch would be on a typical cycle's gas tank. Since there is no clutch or other left hand control, these are mounted on the left side in easy reach of the rider.

The batteries are connected or disconnected with a removable red "key" plunger. Make sure to get a disconnect rated for high amperage. The full current of the vehicle goes directly through this component. All battery cables, fuses, connectors, shunts, shut-offs, and anything else carrying current needs to be sized correctly. Since I'm using a 300 amp motor controller, sizing everything to 300 amps makes sense.

Main Fuse
The bike needs a fuse that will blow and protect the system if anything shorts or otherwise draws too much current (such as a blown motor controller.) I used a fancy-looking fuse holder with a 300 amp fuse in it. Make sure to mount this in such a location that the fuse is easy to access and replace. (If you want to get really wild, make it so it can be easily replaced on the side of the road, in the middle of nowhere, at 4AM in a rainstorm. Because you just KNOW that's when you are going to have a problem....)

Main Contactor
The Main Contactor is a large, remotely-activated, high-power relay. When I turn the on/off key, it sends 12V to the main contactor, which closes, and completes the 48V drive circuit. The contactor is spring-loaded, so that if it no longer gets that small amount of 12v power, it opens and shuts down the cycle. This works well as a safety feature. For example you could wire a switch in series with the 12V power to the contactor from the kickstand. If the kickstand is down, the main contactor won't close, and you can't turn the cycle on. 

Pre-charge resistor
Most motor controllers require a "pre-charge resistor". That's a way to allow power to slowly go into the motor controller to charge up the capacitors. If power was suddenly applied to the motor controller (such as just flipping a switch) the capacitors internal to the controller would suck up power almost instantly. Do that too many times and the capacitors will blow and wreck the controller. If you called the manufacturer for warranty work, the first thing they will ask you is about the pre-charge resistor.
The resistor simply bypasses the main contactor. When the battery disconnect is turn on, current will flow from the batteries, through the resistor, and into the controller. As it does, the voltage internal to the controller will raise to match that of the batteries. Once it does, you can turn the key to on, which activates the main contactor. The contactor is now a less resistive path, and when you twist the throttle, high current can not go from the batteries, through the contactor, controller, and motor, and drive the cycle. Pre-charging the controller also prevents any arcing internal to the main contactor and prolongs its life.

Ammeter and Shunt
The ammeter is a display of how much current (measured in amps) that you are using at any given moment. Think of it as a real-time energy meter. In general, you want to minimize amperage while cruising (to maximize range and battery life) but it would also be nice to know how much power you use for burn-outs and powering up hills.
This is usually a matched set. The Ammeter is the display itself, mounted on the handlebars or other location for easy viewing, and the shunt, which is a calibrated piece of metal that the current flows through. Two wires (one on either end of the shunt) go to the ammeter. The needle on the ammeter varies directly with the amount of current through the shunt.

My ammeter is a 300 amp meter, mounted in a hole in the former gas tank. The shunt is mounted out of the way, near the contactor and battery disconnect. I strapped the gas tank down to a drill press with a hole saw in it to cut a hole just slightly larger than the ammeter. Since the gas tank doesn't hold gas anymore, there's no reason not to cut holes in it and mount instrumentation in there.

I recommend an ANALOG ammeter. A needle sweeping back and forth is easy to quickly read. Although a digital display may be more accurate, it's not as useful and it's difficult to read digital numbers that are constantly changing.

Power Indicator Light
On an electric motorcycle, there is no engine noise or vibration to indicate to the rider or anyone else that the motorcycle is on. You simply flip a switch, and it's instantly ready to go. Although the headlight is on when the cycle is on, the rider typically can't see that during the day. I wanted a great big, bright indicator to tell me when the vehicle was on. I decided that a green light mounted towards the front of the tank would work well. I found some switches, lights, and other components on an old instrument panel. One light had a sign on it saying "Power" and another one had a green lens. Both lights were for AC power, not DC power. I grabbed the components and put together the green lens, the power sign, and removed the small transformer on the bottom of the light socket so I could instead run 12V DC straight to the bulb. The bulb holder was installed through the gas tank, and 12V wiring run to it from the cycle's 12V fuse panel.

Powering the 12V system
On a typical gasoline motorcycle, there is a 12V battery to start the engine and run the headlamp and other electrical. The battery gets recharged by the engine, through the alternator, and it is what really powers all the 12V electrical.
Without an engine and alternator, you will need some other way to run the 12V electrical.

With a 12V battery
If you mostly just use the cycle for very short trips and errands, you could just use a plain, sealed, 12V battery. That battery would need its own charger, so that every time you are done with a ride, the 12V accessory battery gets recharged right away. The battery will take up some space, add some weight, and you would most likely want the charger for it left right on the cycle as well, using up even more space. It does work, and is simple, but not ideal.

With a DC/DC converter
Instead of a dedicated 12V battery and charger, you could use a DC/DC converter. The converter is an electronic device that takes one DC voltage in, and gives a different DC voltage out. It's a very efficient way to use a trickle of power from all four of the large drive batteries, convert the 48V to 12v, and run the headlight and other accessories.

The DC/DC converter was a computer component purchased from e-Bay for $10. It's two-inches square by half an inch thick - very compact and lightweight. This saves considerable bulk and weight over a medium-sized battery and dedicated charger. 48V from the drive batteries is wired to the input end of the converter. The output end of the converter takes the place of a 12V battery. The + goes to the cycle fuse panel, and the - goes to the motorcycle frame ground.

The output of the converter is adjustable into the range of CHARGING a 12V battery, so another option is to use BOTH a DC/DC converter and a small lead-acid battery. The converter provides power to the battery as a trickle-charge, and the battery acts as a reservoir in case you suddenly pull more power than the converter can provide, or in case it quit working.

This DC/DC Converter is rated for 100 watts. The headlamp draws 55, leaving plenty of power for the tail-lights, turn signals, and other 12V accessories.

I crimped and soldered 1/4" spade connectors on the converter to make it easier to quickly connect the wiring. The converter already has mounting holes in it. I mounted it with small screws to the same plate that the motor controller is mounted to.

All over these various components serve important roles. Even though the motor and batteries are the first things we think of on an EV, make sure you understand the balance of system to properly and safely operate your vehicle.
<p>Ben your instructable was a huge help to me in figuring out my own electric motorcycle conversion project, so thanks for sharing! I thought you might be interested to see the instructable I just posted for my project: <a href="http://www.instructables.com/id/Engineer-Your-Own-Electric-Motorcycle/" rel="nofollow">http://www.instructables.com/id/Engineer-Your-Own-...</a></p>
<p>This is my first time on this post. I read a lot of the posts and a lot of interesting info. I have built a couple of Electric KTM dirt bikes, and am now building a Yamaha Steeel frame electric with a gearbox. A lot of the questions that every posted are good, and I have worked thru most of them. My KTM is a 2008 250SX-Fframs and running gear, a Motoenergy ME1004 48V 200-400A motor. I have been using the Kelly controller. I bought over what I needed 72V 500AMP with Regen. I am using a Magura 5k throttle and it works fine. My batteries are CALB 40AH x 16 cells to give me 48V 40AH ( about a 2KW battery pack)</p><p>I get 6 hot laps on the motocross track or 15 miles on the street, I was able to make it street legal in California since it was converted to electric. I did not modify the frame so I could put the motor back on, but I love the electric aspect of the bike.</p><p>It is on EV Albums &quot; 2008 KTM Electric&quot; under Motorcycles</p><p>To answer a few questions , the Kelly controller has been very reliable, and the Regen Braking turns the motor into a Generator, which works great on this bike. At a motocross track you rely on engine braking, with electric you don't have any, regen braking is the answer and you can program in as much in as you want, or you can vary it with a rheostat</p><p>The bike has been very reliable , and a lot of fun . It is neat have and play with it. It is encouraging to see all the people on here interested in electric build of there own</p><p>Dcoxryton</p>
Would it work if I put it all in a mini moto ??
<p>I just recently saw a Trail Buddy converted to electric. It was really cute, and an all the electric components were really well packaged. I didn't see it on their home page, but it was built by these guys. http://www.trail-buddy.com/home.html</p>
<p>You can pretty much build any size electric motorcycle you want, However:<br>1) If you build it really big, you will need a very powerful motor and high capacity battery pack.<br>2) If it's a very SMALL motorcycle, you will have very limited room in the frame for all the components, and will only be able to fit smaller batteries.</p><p>A mini motorcycle sounds like a lot of fun. You could probably get away with using the style of lithium batteries used by high-end RC Car enthusiasts.</p>
<p>I recently obtained an old 1950s Harley Davidson frame from a friends junkyard. It does not have a VIN# because this was from a time before they put VIN#'s on frames. The odd thing about it, is the DRF XXXXX number on it. Does this mean it was stolen? Will I ever be able to register this old of a motorcycle frame before I start building on it?<br><br>Thanks for any help.</p>
<p>Depending on your state laws you will probably be able build it as a new custom. My suggestion is to sell that frame to a collector and buy a complete bike with a blown motor. Old Harley frames are heavy and parts are expensive. </p>
I think the last sentence you said kind of sealed the deal for me.<br>Looks like I'll need to find a Collector! <br><br>Thanks again<br>-TM
<p>I've built a 72 volt version from a Suzuki 600 Katana. weights about 500 pounds.</p><p>This was built in about 1 week give or take a few days. the current picture is Version 3. the first version was a 48 volt 75 Ah system. Version 2 was 72 Volt 75 Ah version, but the final version was 72 volt 101 Ah version. current version gets between 30-40 miles per charge depending on driving conditions. only an estimate since it is only 22 miles to work @ 50 mph and i recharge it everyday at work, so i never really never had a chance to kill the batteries that much.</p><p>This version has a dual laptop battery pack for the light and a 72 volt battery pack for the Drive motor. all lights are custom built L.E.D. lighting that i made my self from 12 5050 L.E.D. strips.</p><p>This version uses about 50- to 65 amps at 50 mph.</p>
<p>I like your electric scooter selling service..<br>http://www.billelectricscooter.com/</p>
<p>First of all, thank you for putting so much time into such an awesome instructable! This is really helpful. Secondly, I have a question. I'm looking at doing this for a 2001 Yamaha R1. It's perfect as the engine is in good nick and the transmission is busted, but I'm wondering if it's too heavy for the electric motor you used. I'm new to EL motors and trying to make a go of it with this project. What do you think? Could it work? </p><p>Cheers!</p>
Hi!<br>Put in few words, with same motor and more amps-hour (more energy stored), go farther.<br>Readequate motor (to get more power - more watts), more amps-hour, more speed depending on gearing. Same range. It's not so simple, you have to equate all variables for your goal.<br>Usually motors with higher voltage can develop more power.<br>Of course the correct is that you have a target power, say 750W (~1 HP), for sake of simplicity: 75V x 10A to feed the beast. Or, 32,5V x 20A. Or 150V x 5A. And it goes on. Higher voltage also allows thinner wiring (to hold less current)if you manage to have a motor that runs this figures at 12V, you would need to provide 62.5 Amps. Imagine the wiring for this now. Research motors, batteries, weight, your goals and spreadsheet it to find your personal solutions having in mind what you want. :)
<p>Wow what A dream bike..<br>I want to build my own like yours. <br>does it become a 96v18ah battery if i connect two 48v9ah batteries?<br>This is what I found on alibaba website </p><p><a href="http://www.ebike-bmsbattery.com.cn/product/690588130-215068276/e_bike_48v_lithium_ion_battery_ups_battery_48v_lithium_ion_battery.html" rel="nofollow">http://www.ebike-bmsbattery.com.cn/product/690588130-215068276/e_bike_48v_lithium_ion_battery_ups_battery_48v_lithium_ion_battery.html</a><br>Lifepo4 48v9ah E Bike Battery,e-bike battery,ebike battery<br>Item No. Voltage Capacity battery type Lifespan <br>BMS<br>Option<br>Charger<br>Option<br>Dimensions Weight<br>G-BP4809A 48v 9ah lifepo4 <br>&gt;2000<br>cycles<br>15Amps 3Amps 69*148*360mm 4.9kgs<br> <br>48v 9ah electric bike li ion battery Characteristics<br>a. Very Security: No fire,no explosion,no leakage ;<br>b. Portable handle and hidden charging port;<br>c. Aluminium alloy Back rack(Silver and Black for option);<br>d. Well die-casting slide board and lock, for easy installation and theft-prevention.<br>c. 30A Fuse and smart BMS are included for protection<br> <br>Pictures and detaild data sheet</p><p>Model G-BP4809A<br>Norminal voltage 48V<br>Rated capacity 9Ah @0.5 C3A, 20&deg;C<br>Operating current 15Amps(can be customized) <br>Peak current 30Amps(can be customized) <br>Charge voltage 58.4V <br>Standard charge current 3Amps <br>Cycle life &gt;2000times <br>Dimensions 69*148*360mm<br>Weight 4.9kg<br>Battery box material aluminium alloy <br>Built in battery cells 3.2V 9AH polymer lifepo4 cells <br>Assembly 16 cells in series<br>Operating temperature - 20 &deg;C to 60 &deg;C<br>Charge temperature 0 &deg;C to 45 &deg;C</p><p>it weights about 12 pounds.<br>What do you think? No one can answer my question.</p>
<p>Hi.</p><p>Batteries Voltage adds up when in series, but current does not. If you put 2 batteries in parallel, you will get same voltage but will add the current. This is very very basic electricity.</p><p>To achieve your 96/18 figures you need 4 batteries, putting 2 pairs of 48/9 parallel batteries in series. I mean take a pair and mount in parallel - call it now pack 'A'. You now have a 48/18 pack. Then take 2 of this packs 'A' and put in series then you have your 96/18.</p><p>Best regards</p><p>Lissandro</p>
Thanks. Sorry for bothering you but if you dont mind i ould like to ask you one more question. Would my bike run faster and run farther if only current(AMPS) goes up? I think there is extra space for a pair. in that case a pair becomes 48v/18ah?
<p>No, current has nothing to do with range or speed. On a DC system, speed is determined by voltage and gearing. RANGE is primarily through battery CAPACITY, which is measured in AH - amp-hours. Being able to draw more current can get you to your top speed quicker (better acceleration) but won't change the top speed.</p><p>If you add additional batteries in parallel, this will increase the capacity of the pack, and give you better range. Current is only related to range in that batteries will give you less total range at high current than low current. Also, if batteries are the limiting factor in how much current you can draw, adding more in parallel will allow you to draw more current. </p><p>Remember that current (measured in amps/ampres/A) is flow, it is a RATE of power use. Amp-Hours (AH) is a measure of capacity. </p>
<p>Questions:</p><p> 1. Why a drive between the motor and the wheel? Why not have the motor in the wheel hub? Wouldn't this be more efficient?</p><p>2. Do you still use a gearbox? If so, why? Cant you use direct acceleration?</p><p>3. Why have a braking system, once the vehicle is stationary, wont it only move if you apply power?</p><p>4. Could you use this same system to make an electric cruiser?</p><p>5. Where can i get an high efficient high speed motor?</p>
<p>Hi Alexander!</p><p>Answers:<br>1: Chaining the motor to the back wheel allows for both adjustable gearing (by changing the sprockets) and for placing the motor where I would like it. Hub motors of the right power ARE now available for motorcycles, but have not always been the best thing for high top speed. Direct drive also doesn't usually give you the same &quot;oooomf!&quot; that you can get with a chain drive. Also, a hub motor increases &quot;unsprung&quot; weight, which isn't as good for handling. My project as of spring 2015 is a Vectrix, which DOES use a rear hub motor, but it also has planetary gearing to overcome some of the limitations of hub motors.<br>(http://300mpg.org/2015/03/02/vectrix-maiden-voyage/)</p><p>2: Please see step 11. <a href="http://www.instructables.com/id/Build-Your-Own-ELECTRIC-MOTORCYCLE/step11/Driveline-Sprockets-and-Gear-Ratios/" rel="nofollow">http://www.instructables.com/id/Build-Your-Own-ELE...</a> It clearly shows that there is no transmission. The motor is chained to the rear sprocket. Yes, it is more efficient than with a transmission, there's fewer moving parts, it also saves space!</p><p>3: Brakes! Yes, of course I have brakes! The cycle came with brakes, I did not change them. Why would I want to remove the brakes! Yes, once at a stop, the cycle doesn't move, unless on a hill. Brakes are most important when you are moving and want to slow down! The vehicle doesn't have &quot;regenerative braking&quot; or any special system other than the stock regular motorcycle brakes.</p><p>4: Yes, you could build an electric motorcycle similar to the say I did, but build it as a standard, a cruiser, a sport bike, a scooter, or whatever style of motorcycle you like. Sport bikes are popular for conversions because of their light-weight aluminum frames.</p><p>5: There are many mail order companies on the web that sell electric vehicle parts. Just do a web search for them. The Electric Auto Association also has some nice links on their web page. <a href="http://www.electricauto.org/?page=EVsForSale" rel="nofollow">http://www.electricauto.org/?page=EVsForSale </a> Scroll about half way down on that page to &quot;EV Converters, repairs, &amp; kit or component suppliers&quot;, you can order parts, including motors from those places.</p>
<p>Dear Ben,</p><p>I have a 1972 honda dirt/trail bike whose engine seems to me not worth restoring, and I have toiling with the idea to convert to electric for the longest time, refreshing my parts wishlist from time to time.</p><p>At last I've seen the Enertrac 18&quot; hubmotor, and its the ideal motor in my opionion. However, as with any electric application, battery technology seems to let us down in various combinations of cost, weight, size, and amperage (cost in particular). </p><p>I have seen your batteries on your Kawa and its damn huge (and heavy). I am thinking of using LiPO batteries from hobbyking (those used in large scale electric RC) - just need your two cents on this opion.</p><p>Tks,</p><p>Aszman.</p>
Hi ErfanA1,<br><br>Yes, you are right, lead-acid batteries ARE heavy. In fact, right now, I'm upgrading my Kawasaki to NiMH batteries I got out of an old Ford Escape Hybrid! (Nickel is still heavy, but it's better, and the salvage yard price was GREAT!)<br><br>Hub motors are becoming practical for EV motorcycles, and have already been used on many EV Scooters.<br><br>Lithium batteries are great. You might want to see about going on the Endless Sphere web forum. Those guys are into electric bicycles, but have GREAT knowledge to share about using small lithium batteries.<br><br>Good Luck!
<p>SUH-WEEEET-AH!!! </p><p>So 'ok...you've got the info I needed and explained clearly...more clearly /less cluttered than most other related instructables! Now can you answer me this...the wires coming from the controller to the throttle.....could an arduino replace the throttle? this would be for remote or programmed motor &quot;control&quot; ie: instead of a human hand turning a physical throttle...an arduino sending signals to the controller as though it (arduino) IS the throttle...? make sense?...others have jumped all over me for this...but I think the 2 wires can act as the potentiometer..? yeah?</p>
On my motorcycle setup, the throttle is a 0-5Kohm twist potentiometer. To replace this style throttle with an Arduino, you would need the Arduino to be able to create a variable resistance in that range. I haven't played around with Arduinos very much at all and would have no idea how to do that, but I'm sure somebody could figure it out.<br><br>There are also motor controllers that use a variable voltage of 0-5 volts as their input. Voltage can be varied by PWM, and I know that can be done by Arduinos. So, it may be an easier approach to use a controller with that style input.<br><br>Due to safety considerations, I would NOT create any kind of &quot;experimental&quot; throttle for an on-road vehicle, but if it is for some sort of stationary machinery, just follow typical safety precautions and have fun!
<p>YES!! thats the numbers I was lookin' for!!! I'm just starting arduino as well but, if I'm not mistaken 5v is exactly what the arduino needs /handles.</p><p>I'm sure a resistor or two would make it a little safer I think? arduino pros?</p><p>the applications of this could be for giant remote control cars, a stationary sculpture...anything an arduino could influence via...PIR sensors..bluetooth phone remote control...timers etc.</p><p>Much Thanks Bennelson!!</p>
<p>I have lots of bikes but I have this 74 cb 360,I took this cbr 600 that I had ,it was from a police chase and it was never picked up from the cops after its rider got away after it slide own on a golf course so I got it after it sat at the tow company for a couple of years..never could get a title for it so I sold its engine and took off its rear swing arm and front forks which bolt directly ODDLY to the 74 cb..I welded on the rear swing arm to make this cafe bike....but Id like to convert it to electric since I have 3 more bikes including the 75 cb 550....which will be cafe also but still a gas burner..I want an electric motor that goes faster than 45 mph..any suggestions?Im going to run lithium batteries Im thinking.</p>
For high speed/performance, it's best to go with the highest voltage motor you can. 72V is pretty popular for a fun lithium bike. Motenergy has some good motors. Check them out.<br>http://www.motenergy.com/
Can you use the existing transmission system of the bike??
On most motorcycles, the engine and transmission are really a single, integrated unit. It's very difficult to remove the engine, but keep the transmission. You CAN build an electric motorcycle with a transmission, but the tranny takes up space that might better be used by having more batteries. <br> <br>What a transmission in general really does is convert engine speed into torque. Electric motors tend to have HIGH torque at LOW speeds, so you don't neccessarily need a transmission. <br> <br>For a commercially-built EV cycle WITH a transmission, take a look at the Brammo Empulse.
<p>How about getting hold of an old pre-unit Triumph (or other manufacturer) gearbox? They are small and lightweight and also very strong mechanically. You should also be able to get different gear cluster set ups at a reasonable price.</p>
But couldn't you gear that high torque down to get better top speed/further range?
For higher top speed, you would use high gearing, which would pull greater amps. Pulling higher amps creates more heat, shortens battery life, and reduces how far you can go per charge.<br><br>In general, to increase top speed, you are best off increasing your system voltage.
<p>Good day Sir, i would like to ask if this bike could be build in South Africa too, and if i may request the plans for this bike please. Would you consider to open a factory here in the RSA ? A lot of jobs can be created by this and you may profit a lot by it too. My email is just1info@gmail.com 073 327 9390 thank you very much.</p>
<p>Good day Sir, i would like to ask if this bike could be build in South Africa too, and if i may request the plans for this bike please. Would you consider to open a factory here in the RSA ? A lot of jobs can be created by this and you may profit a lot by it too. My email is just1info@gmail.com 073 327 9390 thank you very much.</p>
<p>Good day Sir, i would like to ask if this bike could be build in South Africa too, and if i may request the plans for this bike please. Would you consider to open a factory here in the RSA ? A lot of jobs can be created by this and you may profit a lot by it too. My email is just1info@gmail.com 073 327 9390 thank you very much.</p>
<p>Good day Sir, i would like to ask if this bike could be build in South Africa too, and if i may request the plans for this bike please. Would you consider to open a factory here in the RSA ? A lot of jobs can be created by this and you may profit a lot by it too. My email is just1info@gmail.com 073 327 9390 thank you very much.</p>
<p>Hi there,<br>what do you suggest on making a custom frame for my bike?<br>I want to make one!<br>What are the members that are included on the frame??</p>
Actually, I would suggest NOT building your own custom frame! By using an existing, stock frame, it already has a Make, Model, Year, and VIN (vehicle identification number.) These are important to have to title, license, and insure your motorcycle.<br><br>While it IS possible to build a cycle scratch and get it titled, it's complicated (more in some places then other) and possibly quite expensive. Even if you do that, it may still be challenging to get reasonable insurance.<br><br>If you really DO want to build something from scratch, try an electric bicycle. Most places don't require insurance, title, or registrations on bicycles, and it's a great way to learn about electric vehicles!
I'm going to purchase your DVD as soon as I get to a desktop. Thanks sir!
I know nothing about any of this, but this gives me hope. 2k is a reasonable price for the experience of custom made. Great job. Any books you recommend to get me &quot;in the loop&quot;. Thanks, -Steve
The best book out there is SECRETS OF EL-NINJA, by John Bidwell, but it's starting to get pretty hard to find copies. Any book about electric car conversions will get you going in the right direction, as information about motors, batteries, charging, etc all apply the same.<br><br>Also, I made an instructional DVD teaching people how to build their own electric motorcycle. That's available at: http://300mpg.org/electric-motorcycle-dvds/<br><br>Hope that helps!
My key switch can switch two circuits, one like a normal switch and one for an ignition (spring loaded). Which one am I supposed to use?
You just use a regular on switch.
<p>What happens when you release the throttle? Does the motor just keep going in &quot;neutral&quot;, or does it start breaking? Also, do you know what the &quot;plug brake&quot; switch in the controller settings does? (I'm using the AllTrax ControlPRO software).</p>
The vehicle just keeps moving forward in &quot;neutral&quot;. There is no regenerative braking setup on my project. Kelly controllers support regen, but I've never heard anything good at all about the quality of that brand of controller.<br><br>Plug braking is a way to use the motor as a brake by shorting the system. It slows you down, but does NOT regenerate power. It's typically only used on off-road vehicles, such as forklifts and golf-carts.
<p>Alright, thanks! How do know how you activate the plug braking, and how fast it's breaking? We're building a monowheel, so we need a slow and steady breaking and it would be great if we could do that with just the motor.</p>

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Bio: Ordinary guy with no special skills, just trying to change the world one backyard invention at a time. See more at: http://300mpg.org/ On ... More »
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