How to Build a 24 Volt Electric Motorcycle

 

I have viewed a few Electric Vehicle (EV) builds for Motorcycles on Instructables and they all were very helpful. I hope to add to those who have gone ahead and built, shared and motivated me to build one. This is how I went about building this EV Motorcycle.

First view as many Instrcutables, EV forums and Google EV Motorcycle builds. This will give you a good idea of what people are doing. Each time you view one of these builds you may learn something. Here is a list of sites I liked or had some good insight to building an EV Motorcycle and I am sure I will miss some of these tasty bits of information.

Good overall view of how an EV works
https://www.youtube.com/watch?v=dFWEc7Ytq44
https://www.youtube.com/watch?v=ikOqnkIJrLg

Instructables that I used over and over
https://www.instructables.com/id/Build-Your-Own-ELECTRIC-MOTORCYCLE/
https://www.instructables.com/id/Electric-Motorcycle-conversion-48-volt-on-a-budg/
https://www.instructables.com/id/48V-Electric-Flat-Tracker/?ALLSTEPS

Other Sites
http://www.schultzengineering.us/chap2.htm
http://www.electricforum.com/cars/conversions-kit-electric-cars-diy/82-electric-motorcycle-2.html
http://www.gcroa.org/teams/ASU_Maroon_Grand_Canyon/final%20report.pdf
http://www.evalbum.com/
http://www.alltraxinc.com/ (I used an Alltrax controller, use the site for your controller)

Sites I used to purchase items for my EV Motorcycle

http://www.EVDrives.com
http://www.electricmotorsport.com
www.craigslist.org
http://www.amazon.com
http://www.ebay.com/

When deciding what voltage bike to build there are so many variables that I could not possibly list them here. The batteries are the first variable. If you are going to use a 24 volt system some of the options are 2 x 12 volt batteries, 3 x 8 volt batteries or a Lithium pack for a 24 volt system. Some motors may be more efficient at 24 volt. The motor I choose is more efficient at 48 volts but works fine at 24 volt. These variables make it difficult to tell how your EV motorcycle will perform. To get a good idea of how your EV motorcycle will perform is to Google your motor and find similar designed projects that someone has already completed and hopefully they post some performance numbers.

24 Volt bike – would be local only 5-10 miles with a speed of between 20-30mph.
48 volt – local streets, faster and longer range of up to 30 miles with speeds from 30-50mph.
72 volt – can go freeway speeds. (I am amazed that some guys are able to get 6 batteries on a motorcycle.

It seems that many people choose 48 volt EV motorcycles as it seems to have a good price point for most hobbyists and they have plenty of power for local driving.These numbers that I give you are just estimates and you may spend more or less then the ranges I am giving you.

I started a folder on my computer called ‘My Motorcycle’. I created a document to store all of my links that I thought would be helpful. I also started a document that had parts list from other EV Motorcycle. I also downloaded pictures of bikes I liked. Then I started another document with my parts list. At this point I had a clue of what I wanted to do and how much money I wanted to spend.

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I used a site named EVMotorsports.com to get the parts list I wanted as they did all of the work for me (see http://www.electricmotorsport.com/store/ems_ev_parts_kits.php ).   They have kits that list all of the parts that go together.

1) Motorcycle – Plan on spending around $500 for a Motorcycle that has a blown engine or other problems. My son already had a motorcycle and said I could use it to build the EV Motorcycle. I used a 1977 Yamaha xs360. I had to rebuild a front master cylinder that I got from eBay as the one on the bike was not fixable. Look for a bike that has a good frame, brakes and tires.

2) Motor – – Plan on spending between $300-$2000 depending on if you want a new or used and other variables. Do some research to decide what motor you want to use. I picked the Perm pgm 132 and I started searching eBay for the motor I wanted. I purchased this for
3) Controller – Plan on spending between $100 - $500 again search eBay you may get lucky and find a good used one. I ended up buying this new from EVDrives.com along with some other parts because they had the best price I could find for new parts and the I got some help from Carl at EVDrives. If you search some of the EV Forums you will find he has helped others. I choose the Alltrax AXE 4834 and it cost me around $268.
4) Batteries - Plan on spending between $100 – many thousands. I think you have basically three choices on what you can do. Deep Cycle Lead Acic (lowest cost), Advance Glass Mat (AGM) Optima Yellow top are a good example of these, Lithium are the most expensive and there are different types of lithium batteries which I think need special chargers. I choose the two Walmart Deep Cycle Batteries for a total of $136.
5 Other stuff- The other stuff you will need you will probably have to buy new. These items include charger(s), fuses, diodes, contactor, throttle, wire, wire lugs, nuts and bolts. If you have problems with your donor bike you will have to fix those items also. These items will cost you around $200-$500.

Frame 1977 Yamaha xs360                                        $     0  My Son’s Bike
24-72 Volt Perm pmg 132 Motor                                 $ 300  eBay.com
Magura 0-5K ohm twist-grip throttle                            $   49  EVDrives.com
Current Shunt w/ digital reader (did not use yet)         $   20   Amazon.com
Emergency Shut Off Switch                                         $   15  PepBoys
White Rogers style 586 Electrical Contactor  24 Volt  $   45   EVDrives.com
1 Amp Diode                                                                $     4  EVDrives.com
220 ohm Resistor                                                         $     4  EVDrives.com
Reverse protection diode                                             $     2  EVDrives.com
Key Switch                                                                   $     4    PepBoys
Controller Alltrax AXE 4834 w/300 Amp fuse              $ 268  EVDrives.com
2 Deep Cycle Batteries plus core charges                  $ 68+68+9+9 Walmart
Motor Sprockets and key                                            $   26   electricmotorsport.com
Wire 4 awg 15'                                                            $   26   HomeDepot
14 x 4 awg Wire lugs                                                  $   28  PepBoys
Used Master Cylinder                                                 $   10  eBay.com
Rebuild Kit for Master Cylinder                                   $   25  Amazon.com
Steel plate, 10’ angle iron and scrap steel                  $   40  K&H Metals
Rear Sprockets                                                           $     0  Stock
Inline fuse holder – Found in the garage                    $     0
Charger – I had one in the garage                             $     0
Shipping from Websites                                             $ 100
Wire, heat shrink, bolts, paint, tools and miscellaneous stuff from my garage, Home Depot and Harbor Freight Tools.      $   50

I don’t want to add it up but this is a pretty complete list along with the cost of each item

At this time you will need to de-ICE the bike. I marked on the frame where the engine sprocket was located so I could put the new electric engine and sprocket in relatively the same spot. I needed to weld brackets for the motor, batteries and controller so I removed most everything. You can see that I striped the bike down to the frame, tires and chain. I took lots of picture of the wiring in hopes of reusing some of it later. You may want to take everything off the bike at this point if you want to powder coat or paint the frame. I just touched up the paint and left it black as I did not want the hassle of taking every piece of the bike off just to have a perfect paint. At this time I rebuilt the front brake master cylinder.

If you are going to use the stock frame and will not be cutting it up to fit the batteries you will want to make sure the batteries on your parts list will fit. The reason you should mock up the bike at this time is to make sure everything will fit. I have seen people use cardboard to do this or you can draw out all the parts and your frame on paper to see if everything will fit. This was my first mistake I made. I wanted to build a 48 volt EV motorcycle and I did not decide on what batteries I was going to use. I order all of my parts for 48 volts and decided I was going to use Walmart deep cycle batteries. The smallest physical size are big. I realized I was in trouble at this point. I could have bought a different battery that would have fit 4 but would have cost me around $700 more than I planned. I bought a couple of batteries for mock up and welded some plate steal and a to see how they would fit and at that point I decided to just use two batteries as two batteries fit nicely on this bike. I had to return my contactor as it was made for a 48 volt system. My controller was also set up so that it had an under voltage setting set at 30 volts in order to protect the battery pack. A thanks to Steve from Alltrax.com and Carl at EVDrives.com for helping me trouble shooting the under voltage setting. And thanks to Carl for making the return relatively hassle free. Many other EV motorcycle builds will have some great suggestions or build a bike that someone else has already done.

At this time you should have decided on the voltage of your bike. You should have completed your parts list. Like I said earlier, some parts are designed for specific voltage. Now start your searching for the best price for the parts you need. The first thing I found was the motor I wanted on eBay. I was very lucky to find the motor with only an hour of use. When you buy used parts there is a chance the parts may not work, when buying from eBay try to buy from sellers who have sold a lot and have very high percent of positive feedback.

I mocked up my bike and knew that I was going to be welding both a motor mount and battery trays. I had to cut a few motor mounts and other tabs so the batteries and other components would fit nicely. There are other Instructables that claim to have no weld builds but I will tell you that it made my build much easier to weld the brackets I needed. I have an $89 Harbor Freight 90 Amp flux welder and an Acetylene/Oxygen gas welder. I am not great with either one so I used both welders on this project. I first welded some plate steel on the bottom of the frame to mount my motor mount plate. I cut another piece of plate steel for the motor mount. I tried to make the plate somewhat adjustable and removable. Then I cut up the angle iron for the battery trays. The second shelf was the hardest and I think I was very lucky the way everything fit. I ended adding another bracket to the top of the motor mount plate as when I rolled the bike around I could see the motor mount plate was shaky. I created a shelf for the controller and a small battery for the lights and horn. I used the inside of one of the side covers to hold the shut off and contactor.

This was made easy by the vendors and those who built EV Motorcycles before me. I bought an Alltrax controller and it came with a fuse. On the Alltrax web site I found a schematic for the controller with the Magura 0-5K ohm twist-grip throttle. The contactor had the option to buy with the diode and resistor so I did. I also knew I needed a reverse protection diode from the schematic so I ordered all of the parts that I needed at once. Basically your controller’s documentation will give you the plans to wire your EV Motorcycle. Depending on the voltage, the wire and wire lugs will have to be thick enough not to melt. I found this information on many web sites. I do not want to make light of this part of the build as it is dangerous and could be expensive if you wire it up wrong. Use the help from your controllers web site and the site you buy your electrical supplies. I don’t want it to sound easy, it is very helpful if you can read the schematic or have a friend who can. I had some basic tools and a multi-meter. I soldiered all of my connections and used heat shrink to make it look nice. It ended being the most frustrating and rewarding part of the build as I have worked on Motorcycle but have never built an EV Motorcycle.

I still have a few things I am working on before the bike can be ridden.  I will need to work out any bugs, lights and charging. When all of the bugs are worked out I will give my son his Motorcycle and I will start to convert a car. I think this was a good experience and my knowledge gained on this will go towards my next project allowing me to convert a car more confidently and hopefully more cost effectively.