Motorcycle Conversion

Today was a great day. A big victory in my little EV world. I rode the CBR to my friends house. He just about flipped out. "Dude! Your NUTS! That thing is cool! You totally snuk up on me!" ( he was working in the yard when I silently drove up).
My 14 year old niece came over for the day to visit, and I gave her the very first ride as a passenger on the bike. Pretty neat. Then she drove every other EV we have, taking turns on each one all day long. It was a great EV day, and all 5 EV's were running great.

Just for the fun ot it, we added up the total voltage for all 5 EVs. It adds up to 228 Volts. I guess what separates the men from the boys though is Amps right?
Also, Friday night we took the Elec-Trak electric tractor to the local fair, and pulled it in the garden tractor pull.
What a blast that was. The announcer had a lot of fun with it. He would tell everyone in the crowd, "now everyone be quiet and listen to this motor run". My wife said the whole place went silent! The tractor pulled 93 feet, and the longest pull by a well tuned ICE tractor was 107 feet. Out of 15 tractors in the class, the Elec-Trac finished about 10th, with only about 5 feet in distance separating the rest of the field. The people really enjoyed watching it pull, and I was approched by several that had never seen one, or remembered them years ago. I went home with another big giant EV grin.
Thanks again to all who posted such great and useful information, and taking the time to explain things in laymans terms, separating fact from fiction, and good product recommendations.
I hope to provide some video and speed/range data as soon as the CBR is registered for the road.

Well another 3 weeks have passed, I am still not riding YET. Other, more important things have taken up every spare minute. The garden is in,

my oldest graduated from high school

went to Cedar Point Park in Ohio,

and I was heavily involved for almost a week in the moving of our work place. Now I have a 6 mile commute to work. AND my youngest son broke his arm at Scout camp. He is expected to make a complete recovery. Mostly his pride hurts more than his arm .
So finding time to work on the bike has been difficult.
Here is the current status:
2 weeks ago, I went for a short test ride . My batteries were very low, and everything was hooked up temporary, kind of hanging all over the place. The bike was slow, but I was able to test the low speed handling and balance. I was very happy. A big EV grin . In the process of changing out some of the bad batteries, I shorted out the controller to the frame, and fried the controller . A major rookie error, but that is part of the reason I took on this project, to learn by doing. I have since learned that I MUST disconnect the B+ connection from the controller BEFORE servicing the battery pack. What this has done however, is give me time to complete the balance of the work on the bike, while not being tempted to just ride it, and worry about finishing the "little" things later.
A few days ago, I started the final installation of the body work.
Thursday, July 3rd, I finished the main charging station.

I used a 9 pin trailer style connector, and installed the female side on the main cowl of the bike.

July 4th it was raining here most of the day, so I was able to work on the bike all day. I finished the dash by installing a cycle computer and the Pak-Trakr.

I really like the Pak-Trakr. It is an amazing little tool. For the cycle computer, I chose a Panorama v-12. I used JB QUICK WELD to attach the magnet to the bike wheel. The sensor tie wraps to the fork, and the fender covers it all up so it is protected, and not visable. The display will be attached to the face of the dash with HD velcro.
I have finished the installation of the 2-Power Stream 36 Volt onboard chargers. They fit nicely under the tank. The batteries balanced out pretty well while charging. The Pak-Trakr was very helpful during the testing of the on board chargers. I am in the process of making the extention cord storage area in the tank, so the cord will come out of the gas cap.

So now, as soon as my controller comes back (hopefully by July 12th) I should be able to ride with everything functioning and complete.


That's it for now. I hope my next post is with speed and range information.
I just wanted to thank all who post on this forum. I have used a TON of info from this site. Many of you deserve much thanks. Thanks for the encouragement along the way, and thanks for taking the time to check out my project blog.

Over the past couple of weeks, some forward progress has been made. I was able to finish the re-sealing of the front forks. I had to special order some bolts that were destroyed during dis-assembly from the Honda dealer to finish the job. The new front tire has been mounted and balanced, and the front end is now back together. The D&D ES-15A motor arrived last week, and I spent the better part of Saturday making mounts. The motor mounts are done! The motor is in position and ready to be wired.

The chain has been cut to length. I purchased a 520 motorcycle chain so it would fit the rear sprocket correctly, and modified the #50 pitch front sprocket to fit the chain. .100" had to be removed from the width of the #50 sprocket, and the slight angle on the tip of the teeth had to be redone.

To get the motor shaft exactly in line with the swing arm, I had to notch the frame 1/4". I did not want to do it, but now that it is done, it was worth it.

I welded in a piece of steel to put the strength back in, and painted the affected area.


The motor fits nice, and looks like it belongs there.

I had to modify the fairing just a little to clear the motor. The motor does not stick out any further than the ICE, it is just raised up a litte higher than the ICE transmission case was.


All the electronic arrived Saturday. I ordered everything from Kelly Controls, and it all was shipped from China. It only took about 2 weeks from order placement to arrival. I was very pleased. Now it is time to mount all of this stuff.

After reading through the instruction guide for the controller, I realized the throttle input on the high power Kelly controllers needs a 0-5 Volt throttle. OOPS. I waisted some time and money on the PB-6. I have found a 0-5 Volt potentiometer used in race car data aquisition systems. It is very rugged, and easy to adapt to a throttle cable. It's a little more $ than a PB-6. But it should last forever. That's it for now. I hope to get to mounting the electronics and get some basic wiring done this weekend. The next major plung will be batteries and chargers. Just wanted to thank all who have helped with info and encouragement, and interest! This is getting very exciting. A test ride could be just a week or so away!

First I have 2 motorcycles. Both are Yamaha 650's that I bought off ebay. I went to ohio for this bike...

Love the way it looks Just had to have it. Only thing needed is the carbs cleaned. They are being done now at the shop.

Went to Ct. for the parts bike. got to visit my brother when I was there and stayed over for the night.

This is the parts bike.

A week ago I decided to convert the parts bike, and would put parts aside for the first one so I took a couple hours and stripped it down.

First I took off the seat, tank and side covers, then the exhaust and carbs and the battery box and air box came off. I set them off to the side.

Took off the harness and then found I had to remove the headlamp to get the harness off the rest of the way.. Started to slide the engine out but it wouldnt move, there was an obstruction up front so I started to unscrew that and oil dripped out. I drained the oil and removed the air filter. (can you tell this is the first time I ever worked on a motorcycle? normally I send it to a shop, but I have a book now and am learning more all the time). I slid the engine out and it caught on the kickstand which went down as I lowered it. I wiggled the engine off the kickstand and was done with the hard part. I went to move the engine and found I could only lift it a couple inches off the ground so the kickstand must have saved me from dropping it when I slid it off. I moved the engine aside and here is what I had...

I couldnt pick up the engine to move it so I ended up moving it a little at a time to the side of the driveway and it is still there with a wash tub over it til a friend comes over that an help me pick it up. I put all the parts in the shed, put the seat, gas tank, and sidecovers back on and it's ready for the motor, controller etc and batteries.

Now Im on hold while I raise the money to get the parts. I found a kit with all the parts I need already to go, it will be about $1600 total I have a link for that on my post. Then the batteries look like they can be anywhere from $300 to $1200 depending on what I go with. Think it will have to be the cheap batteries for the first round, then later on when I get money again I can upgrade them.

I want to thank all of you folks who gave suggestions and links in my post, and told me about making a blog.
This is my third try to get the blog in. First time it didn't submit because of a bad connection or something and when I hit the back button to try again it said page expired. Second attempt I was almost done and a cat jumped up here and closed my window. I am now going to select all and copy in case something else happens when I hit submit so I dont have to write it all again LOL.

Feb 8, 2008
I've started a project that I hope will have me commuting to work, when spring arrives, on an electrified motorcycle. I've owned a couple motorcycles and now ride a Triumph Bonneville 750cc. The Bonnie is a great bike, but I'd like something 'greener'.

I began by buying a Kawasaki 400 from someone here in Syracuse.
It has a disc brake up front and a moderately heavy frame which I think will accept the weight of the batteries. I've removed all of the ICE parts and gas tank hoping to sell bits and pieces. so far I've recouped 90% of my purchase cost.

I have not bought any parts of the conversion yet, just been doing lots of research here and other places on the WWW.

My plan is this, so far: MARS Electric motor (mounted under the seat - above the swingarm), a Sevcon controller, belt drive and separate LED lighting powered by something like the new DeWalt LiFePo 32v pack. I think I'll try a 48 volt system
(maybe 70 Amp hours per battery) and see how it goes. No solid thoughts yet on the BMS/charging portion or the gauges.

For now, all I have for pictures are the donor bike on the trailer &
then stripped of all Kawasaki motor and in the workshop.

I got my batteries delivered on Friday. I now have about 360lbs of lead to play with! Along with a whole bunch of other stuff and I need to fit it all in that poor, unsuspecting 750 frame...

I went to the local metal supply shop and bought some 1/8" strap and some L shaped as well. I've been playing around with specific mounting strategies in my mind for a while - now it was time to try them out for real. So far, touch wood, I've been reasonably happy with my progress.

The front four batteries are now in place. The lower three are held together by 4 L-shaped corners fastened together with 5/8" threaded rod. Four flat straps are used to provide top and bottom support and to form the third and fourth side of the box. The middle bottom battery rests on two brackets (made from the strap) which attach to pre-existing motor mounts. The fourth battery sits on top of the middle battery forming an inverted T. I'm reasonably happy with how it has turned out so far. I need to fasten the bottom middle battery to stop side to side and back to front movement - I plan on using more brackets made from flat strap and attached to the engine mounts and four more threaded rods. The additional straps will fasten to the frame and spread the load from the existing two straps (four bolts). The additional rods will be longer and will also fix the top battery in place.

The battery on top will also attach to the frame - different frame attaching point than the bottom battery - not sure on this yet. I'm holding off on mounting this top battery and the fifth battery (which sits over the top of the motor) until I've fitted the motor. I'm in process of ordering an ADC motor 6.75 inch diameter, 11.3 inch body length (not including shaft). It's rated at 8hp continuous, 35hp peak. It's a base mount motor and I'm hoping that I can simply attach a floor between the two frame rails and mount the motor to that. Not sure if I'll get the floor welded in place or whether I will drill into the frame and bolt the floor in place (Bidwell's El-Ninja uses lots of bolts in the frame). If I do go the drill and bolt route then I'm starting to think I might be able to complete this without welding (that was the original goal after reading Bidwell's book - but then I started to doubt the feasibility of this approach.)

Here's pics of what I've done so far. Bear in mind that nothing is finished or tightened down - it's still very much in the design stage. I sure wish I had access to a full metalwork shop and that I had the skills to fabricate better brackets - but seeing as so far I've used nothing more than a drill and a hand held grinder I'm pretty pleased with myself! (I run the risk of "pride before the fall"...)

OK, so it is kind of wide! Maybe I should have one of those "Wide Load" signs? I could have made it a little narrower (maybe 26 or 27 inches rather than 28). The original motor was about 23 inches at it's widest point but the bulk of it (the cylinder block) was probably more like 18 inches wide. Ah, whatever, at least the weight is low. This represents a little less than half the major weight addition - I have another 3 batteries to add and the motor (which is 60lbs of fun).

Hmmm, at the moment I'm actually starting to think I might be riding this in the spring... (this is by far the most ambitious mechanical project I have undertaken so I've approached it with a healthy dose of skepticism!).

Battery and Motor Layouts

The following pictures show my trial layouts using 55Ah batteries and an ADC motor (6.75" diameter, 11 inch length). The box for the batteries includes the terminal height and is also oversized by 1/4 inch (the internal measurment is the external measurement of the battery).

My design is now at 84V - which requires seven 12 volt batteries. When I researched my options I found out that a 96V capable speed controller was going to cost me about $1200. I found that Kelly Controllers do an 84V model for $389 - I need an extra DC-DC convertor in their circuit (the control voltage needs to be 24V).

Now, if I could manufacture real batteries which were this light I'd be a VERY rich man and I could use a Zilla (which is closer to $2000).

Layout One
This is my favorite layout. It packages 5 batteries within the frame rails in a simple to implement box. Two other batteries would go as saddlebags/paniers - I will probably make larger paniers so that I can mount 7 seperate 12 volt battery chargers on the bike (not sure about this yet). I feel comfortable that the weight distribution is appropriate (the batteries are 38.5lbs each and the gas motor was over 180lbs (I broke my bathroom scale trying to weigh the motor!). So the majority of the weight is where it "belongs" - in the engine bay and as close to center and as low down as possible. Also, no changes to any of the foot pegs or rear brake lever is needed - so ergonomics aren't affected. The downside of this design is that I can't run a chain directly from the motor (mounted where the battery and oil tank used to be) to the rear sprocket. The swing arm gets in the way - and there's no way I want to modify that. So, I'd need to use a jack shaft - and I'd need to figure out where to mount it.
Layout Two
Next up, layout number two, places the ADC motor so that the output shaft is approximately where the output drive of the gas motor was. Above it are the two side by side batteries which were on the bottom before. The fifth battery is where the ADC motor was in layout number one. This still keeps the weight centered, and the ADC motor is 65lbs so the weight of shifting two batteries higher vs. bringing the motor lower pretty much cancels out. The battery placement is more tricky now - but not too bad. However, this design is "tight" - until I get the real batteries I'm not confident I can make this all fit. In the photos the fifth battery is resting on the rear tire - however, in real life it will mount an inch or so higher. That gives some clearance but not enough. To make this design work I need to shift all the batteries forward slightly - to do this I'd need to grind away the "back side" of a bracket up by the front of the gas tank. I'm pretty sure that won't affect strength - but I'm still not sure I'd end up with enough clearance for the rear wheel (I can also put the rear wheel towards the back of the chain adjustment slot (and sacrifice adjustability). Another area where this design is "tight" is around the right foot peg and brake pedal. I will need to bend the brake pedal out - I might be able to leave the foot peg alone - or I might not. I don't think either of these are a deal breaker.
Layout Three
Layout three addresses the concerns of not having rear wheel clearance for the fifth battery in layout two. I've mounted one battery on top of the ADC and between the frame rails and then I've mounted two batteries outside the frame rails next to the front stack of two batteries. As I look at these photos I realize that I should move those outside batteries lower to get the weight lower down. I'm also a little concerned about putting too much weight too far foward on the bike - however, it's still within the profile of where the original gas motor was. Obviously this design sitll suffers from the "tightness" around the right foot area.

Front Profile

This last picture shows the front profile of the bike. It's for layout #1. Note that the ADC sticks out "a little bit but not too much" (hey, I never said I was an automotive engineer - this is as accurate as I get at this stage!).

So there you have it - three contenders. Any thoughts on which are best? Or a completely different set up? Feel free to leave comments or send me an email or PM (both can be done through links on this site). At the moment I'm thinking layout number three - but we'll see.

Finally, I'm trying to decide whether to look more at batteries to see if I can find something with higher Ah that I can still get to fit. I should probably do some more checking on the specs of my chosen Universal Battery UB12550 to see if they're up to the job...

Stop Press
The Universal Battery UB12750 (75Ah AGM) is the same height but 1.2 inches longer and 1.2 inches wider. I can fit them in the same basic layout as layout three above with the battery "on top of the motor" extending further back into the battery box compartment.

Well, when I'm not reading the daily soap opera posts (and participating from time to time!) over on the message boards I have made some progress with the CB-750. At the moment the new front runner is a 96V system, based on 55Ah UB12550's and an ADC MT2113.

Here's the original 72V graph, followed by the new 96V graph:

I'm not sure I can go as small as 9 teeth on the front sprocket - I need to check into that. If I can't not sure whether I'll just go as small as possible and settle for a higher top speed and less acceleration or whether I'll get a larger rear sprocket.

The 8 UB12550's fit better on the bike than the 6 UB121100. But, of course, I sacrifice range. The 6 110Ah's were a definite stretch in terms of packaging and overall weight. Plan was 4 in the engine compartment and 2 as saddle bags. With the 55Ah's I can get all 8 in the engine compartment. However, that might mount some of the weight a little too high - so I might go 6 up front and 2 in saddle bags. Of course, I could go with 120V and do 8 up front and 2 in saddle bags (or go completely mad and put 4 in saddlebags for 144V). OK, I'll stop getting greedy - and go forward with the idea of a 96V / 55Ah combination. However, I will check into motor options to see if I can find a motor rated for up to 120V or 144V and a suitable controller as well. That way I can start at 96V and then go crazy later if it doesn't all end in a nasty mess before then.

I'll post some pictures of the two different sets of battery configurations.

Next up:
1) Research 96V capable motors
2) Mock up motor and motor mount
3) Mock up battery box

Oooh, it's exciting isn't it?

OK, so I found a round tuit down the back of the sofa and decided to use it for calculating some numbers for my CB750 conversion. I've created a spreadsheet based off of Bob Brant's Build Your Own Electric Vehicle and John Bidwell's Secrets of El-Ninja. I used BYOEV for the required torque formulas, and I used El-Ninja for the available torque formulas (they were presented as a nice short list in the Bidwell book!). I used the co-efficient of drag and frontal area figures from the defaults on the electricmotorcycles.net calculator (http://electricmotorcycles.net/modules/toolbox/battery_worksheet.php)

You can see the spreadsheet at: http://www.editgrid.com/user/jdh2550/CB-72V - if you want to use it yourself then you can get a free edit grid account (takes 5 minutes to setup) and do a Save As ... and create your own copy because you can't edit this sheet directly. BTW, the graph is on the summary tab and all the gory details are on the calcs tab. The other tabs are all work in progress.

Here's the pretty picture I drew:

The lines that run "left to right" are the required torque for various gradients (from level through 25%). The lines that run "up and down" are the available torque for a Perm 132 @ 72V - these are plotted for 3 different ratios (1) the original ratio on the bike right now; (2) the ratio Bidwell uses for El-Ninja & (3) the ratio I'm thinking will be best for me. So, where the "up-down" line crosses the bottom "left-right" line is my theoretical top speed - around about 66mph. The tick marks are at 25A intervals - so I'll be drawing around 120A @ 66mph. The Perm is rated for 110A continuous - so I reckon 60mph should be fine. I figured the available torque by calculating y=mx+c equations for the speed and torque values off of the 72V Perm chart. I only had a small chart so I upsized it and then used a ruler to measure off the values - it's close but it certainly isn't spot on (I don't even know if the torque and speed lines are really 100% linear).

Bottom line is that this exercise tells me that I'm not crazy - I should be able to get a 60mph cruising speed out of the beast without frying the motor. It also tells me that I'll likely be out accelerated by a Festiva By my reckoning I'll be able to accelerate at around 3.5 mph per second - which gives a 0 to 60 time in 17.1 seconds (btw, does anyone know why it's the de facto standard to use 0 to 60? - just curious). With that accel I'll be drawing 400A which will push the poor little Perm if I do that too much.

Update
OK, so I used the chart provided for this motor: http://www.evparts.com/shopping/product_details.php?id=533&product_id=1107 (as suggested by Andrew - thanks!). I read off the values for torque and rpm given amps between 25 and 325 in steps of 25 - yes I am that anal! Added them to the graph above. Getting kind of hard to read now. A couple of points to mention - the top two speeds for the original ration for the ADC have been truncated - so when counting "ticks" one has to start at 75A not 25A. The relationship between amps, torque and speed is clearly not linear for the ADC - yet I calculated as linear (and it's darn close according to this graph which I used as the basis for the calculation).

I'm a little nervous that my available torque curves are bogus. But, what the heck - at least it's not a billion dollars worth of Mars rover... So, I'm pressing onwards with what I've got.

Approximate values for top speed for both motors for my proposed ratio are:

So, the ADC will turn faster at higher amps - however, at 150amps I'm 50% over the continuous rating (listed as 100A). The Perm will give me a top speed of 65 at 125amps, this is only 13% over the continuous rating (listed as 110A).

In Summary: At the moment I plan to use a Perm 132 @ 72V with UB121100 batteries - using a 13 tooth cog on the front sprocket and sticking with the 48 tooth cog on the rear wheel.

Of course after doing some battery math I might change my tune...

Next Up:
1) Start poking at Peukert's law to try and figure some expected ranges (although Bidwell offers twovery simple rule of thumb calculations (a) 30mph steady state range = pack kWhours * 9.8 & (b) stop-and-go range = pack kWhours * 7). This will be the subject of an exciting new blog entry... (I bet you can hardly wait, eh?)

A big thank you to Jason and Jennifer! I picked up Jennifer's 1973 CB-750 this weekend - after a decade of no use they decided it was time to say goodbye. I promised to ride it back under electric power - but not for a while yet!

This weekend was spent stripping down the bike. It went remarkably easily - I mean I didn't even skin any knuckles! Getting the motor out was the biggest challenge but as of 3pm this afternoon the bike lost the last of it's old, loud, smelly, inefficient, oil burning, carbon dioxide belching parts. Know anyone who needs any CB-750 engine parts? Craig's list here I come...

Now that the bike is stripped down I want to weigh it and start mocking up cardboard components (batteries, motor, controller) and figure out placement. My goal is 60-65mph top speed and a 50 mile range. Not sure how close I'll get - but that's the goal.

My current plan is a 72V system. I was thinking of going with a Perm 132 motor - but Andrew has got me considering an ADC motor. The ADC's aren't as efficient or as high powered as the Perm - but they are much more robust. If I go up to 96V I could drop the amperage further - but I just don't think I can squeeze on eight batteries of sufficient Ah.

So far so good - but of course this was the easy part...

Next up: Doing some math (should make Mum proud - she's a retired math teacher!)