racermike39's picture

Well this is my third EV project. I was so encouraged by the results of the Kawasaki 4-wheeler conversion, that I knew a daily driven street vehicle was within reach. I sold my ICE race car last fall, and decided to devote the $ to an electrtic vehicle. I calculated and researched cars, and decided that a car at this time was not within reach financially. With permission from my wife, I decided on an electric motorcycle. I researched this forum, the Austin EV website and many other links to nail down the voltage, frame and bike size. I was inspired by many, mostly by JDH2550's CB750 conversion. The information and links from his blog were most helpful.
I started looking at sport bike frames in the 600-750 range. My goal was to purchase a bike that had disk brakes, good aerodynamics, and stout enough to handle the weight and have room enough for a 84-96 volt pack. My first searches were for a cheap donor. What that led to was long drives to look at junk. I later upped my threshold of spending on a donor. In the end, I wanted a bike that looked good, was reliable, good part availability, supported well by the aftermarket such that when it was completed, it would represent a well designed and performing EV. I want to build a bike that could be sold for reasonable money, to possibly finance another EV, and sell it with confidence that it was with good quality, matched components.

Here are the goals.
96 Volt
26 mile commute with 8 miles highway, and 18 miles 30-45 MPH secondary roads. Charge at work.
50 mile range at approx 45 MPH.
70 MPH capable.
Rides to the beach with my wife. 30 mile round trip.

The donor search ended with the aquisition of a 1997 Honda CBR 600 F3. A very good running clean bike, only needing front fork seals, chain and rear tire. We found it on Craig's List. This is the night we brought it home.
We have removed the ICE, and work began to try and fit 8 UB12550 55AH batteries in this frame.
I was conviced I could model the bike in my CAD system (SolidWorks)and determine where all the batteries would/could go. What I quickly learned was they wouldn't fit. I did not want to eliminate or modify the factory body work such that it was obviously electric. I was also trying to maintain the aerodynamics. The SolidWorks model proved that it would not work. Also I was loosing patience measuring and modeling. Here is the SolidWorks model I used:
This is the configuration I will use. However, I did not arrive at this configuration as a result of the CAD model. I had to do the battery oragami as did JDH25550 did on his CB750.
As much as I tried to avoid this excersize, it was the only way to be sure it would work.
This confirmed what the CAD model was telling me. I realized I would have to modify the lower fairings to get all the batteries in. I found that the lower fairing needed to be widened 4-1/2" to allow the space to be filled with batteries.
From the side and even the front, the fairing did not look rediculous. This allowed the batteries to be positioned such that 8 (96V) would work. Up to this ponit, 72 Volts looked to be all this frame would handle.
Here is a shot with the tank in place. The tank has not been cut out yet, so I will have additional room for the controller, contactor and DC-DC converter.
The only modification so far was spreading the fairing, and trimming out a protrution that in the fairing that was costing about 2" of battery room.

Next I was able to use the factory manual to get rid of the engine management computer and wiring. I also mapped out the wiring for using the key switch to activate the DC-DC converter, and the run/stop switch to activate the contactor. I think I stole those ideas from andrew on this forum.
The next step is to get the motor here and get it mounted. I will keep you posted as things develop.
Thanks again for all your help!

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Mike, good job fitting the batteries. I calculate your desired range of 26 miles is possible with that many batteries.

Your top speed should be easy to achieve. Good luck with getting it working. It'll really be a unique electric bike. Few if any bike conversions have that much battery capacity with lead-acid.

Anyway, please don't use my circuit breaker idea. I need to modify my bike thread and warn readers. After a discussion on the EM listserv I was informed that a circuit breaker is not a reliable manual disconnect. I'm changing my setup to use my Albright SW200 as the emergency disconnect.


Good looking bike! After you notch the bottom of the fairing so all the batteries can fit, one option might be to set styrofoam blocks sticking out the notch-holes. Shape with a razor and sandpaper, then cover with metal mesh and fiberglass. Cut out the styrofoam, add some bondo, primer, and some matching factory touch-up paint (available from a Honda dealer) and it should look pretty good.

If you can't drop in batteries from above, you could make one side with a removeable section.

I think its smart to start with the batteries you are using. Once the conversion is complete, and if you like the performance, you can upgrade to Lithium for a lower weight and more cargo space in the future. A properly spec'ed controller and motor should last for many years without any need to replace them.


Mike, btw, why are you using universal power group batteries? Is it because you have a good source for these cheap?

B&B carries a line of batteries called MPL that have a 55ah size that is very close to the universal 55 ah battery.


Thanks Andrew. I was actually heading in that direction. I left the clutch cable intact for that reason. The only thing I was worried about was to be able to reset it, I would have to take the tank off. I am however going to power up the contactor with the engine run/stop switch on the factory throttle control. So I can dump the contactor with a flick of the thumb, and keep both hands on the bars. I am going to a battery wholesaler soon to take a look at what they have avail. B&B is on my list. I did nt know about the MPL I will have to look into it. Powersource also has a similar battery.

Spinning magnets: I am going to cover the vents and holes in the factory body panels with either thin aluminum, or some plastic sheet we used to build ground effects on race cars with. I hope to totally hide the batteries. The factory air cleaner box has a "ram air" duct work that will supply the controller with cool air. It has provisions in it from Honda that will divert water if I get caught in the rain. Pretty cool!

Thanks again!


I went with universal power because they were the cheapest I could find that had some history in EV use (there were a couple of people in the EV car world who had used them and were happy with them).

I bought mine from Northern Tool in the end.

Mike - your CAD model looks great - I didn't have the patience for that so I just went straight to the polystyrene - of course your bike looks MUCH prettier than mine. Sigh... ;-)


Well the past couple of weeks have resulted in taking the bike further apart. I removed the back wheel and had the new tire mounted and ballanced, and installed the 54 tooth rear sprocket.
The front forks needed new seals, so the front end is torn apart, and the forks are being rebuilt. I also had a new front tire installed.
I took the opportunity while the bike was this far apart to clean and paint the frame.
I chose to use a PB-6 throttle pot, because I wanted to retain the engine shut off thumb switch on the throttle assembly. This is a (blury) pick of the bracket I made to get the throttle cable connected to the PB-6.
The motor (D&D ES-15 A) should arrive today. All other parts have been ordered except for batteries and chargers. The PACTRAKR arrived Saturday. Nice little unit!
The rest of the time since my last post has been spent melting the credit card.
I did manage to sell off all the ICE parts on E-bay. I recouped all but $150 of the purchase of the donor bike. It was well worth the effort to search out a good clean running bike.
I hope to start mounting the motor as soon as tonight.
I purchased a 520 motorcycle chain (NEW) and a #50, 13 Tooth sprocket for the motor. I just needed to take .100" off of the width of the #50 sprocket to work on the 520 chain. That's all set and ready to go.


great job on recouping the cost... thats exactly what I did..... the donor was actually free after parting it out. Gotta love that.

Let me know how you like the D&D, I have the equivalent ADC K99-4007 (Same thing as a K91-4003, just a different shaft).

What are you doing for charging?


Hey Thanks!
I just received the motor about 2 hours ago! Nice looking motor. Well packaged.

I chose the D&D because it has more power (Tim Allen wannabe).

I can't wait to get it mounted! The motor is going to drive the location of everything else, as it is mounted in the "belly". This will help determine the exact location of the batteries.

I am planning on doing (6) B&D 2/4/6 Amp chargers. They are at Walmart right now for $29 each.

I am planning on using (2) 36 volt Power Stream 3 Amp units for onboard chargers. They are fan cooled, and reasonably priced. $48 each shipped.

Hey, I have a question for you. What do you think of the silicone batteries? They are not that much more money. Is there any benefit? They offer a 60AH that looks like it is only slightly larger than the 55 AH SLA AMG. I can't find a whole lot of info on them. I am either going to use B&B (Thanks Andrew) or the silicone. I still have some time before I need to order them. That's the last big ticket item to purchase. I still have to find out if the correct battery from B&B is the "multi purpose" or High rate". Any thoughts?
Thanks again!


I was thinking of the MPL55-12 battery from B&B. Here is the battery: at Zbattery. Here's the spec sheet: MPL55-12 pdf.

But, I was looking at your required range that you posted earlier, and these will probably not work! Here's what you posted, and I'll add my comments:

26 mile commute with 8 miles highway, and 18 miles 30-45 MPH secondary roads. Charge at work.

26 miles would barely be doable with 8 of the above MPL55-12 batteries by my calculations.

50 mile range at approx 45 MPH.

Conservatively figuring 120 whrs/mile all things considered, than this would take 6,000 whrs. This is much more than eight of the above 55 ah batteries could provide.

70 MPH capable.
Rides to the beach with my wife. 30 mile round trip.

30 miles would probably be out of range, unless you ride slow like <40 mph, and are really light on the throttle.

The cost of the B&Bs would be pretty high up there too considering shipping costs included. You may consider some LiFePo4, which would probably be a much better option. Some people are doing group purchases of thundersky LiFePo4. Also, there's some that have recently been put up on this site: Cloud EV LiFePo4

With the LiFePo4 I calculate the cost to probably be not far from double the AGM option for the same energy storage, but these will be so much lighter, and they should last quite a bit longer. Also, you could construct a pack to provide all of your range requirements. Here's one that would do it with the cost:

24 of the Cloud EV LiFePo4 100ah 3.2v in series, at a cost of $4,800

And, here's a Thundersky pack that would probably provide about 30 miles range:

24 60ah 3.2v cells in series, at a cost of $3600 retail. Maybe much less with a group purchase.


Hey Andrew, Thanks for all the info.
I have recently recalculated everything and I reached the same conclusion that you have posted.
I understand the 50 mile range is far to reach. I have cut my expectations back, I also understand that the 26 mile commute is not going to be a reality at 80% depth of charge. That's OK.
I will probably try it and avoid the highway, and stick to the secondary roads at lower speeds. Some real self control will be necessary. (throttle input).

The ride to the beach with my wife will be at <40 MPH. I will probably be OK there. Fairly flat roads also.

I have looked into the Cloud EV batteries. I talked with them a couple of days before the LiFePo4 battery website was released. I was under the impression I would need the 200AH pack in order to draw the amount of current required. That puts the pack cost at over $6K. I still haven't gotten familiar or comfortable with the AH pack required for a particular current draw from a LiFePo4 pack. I say that because of some of the posts where controllers are asking for more than the BMS will allow, and the result is cut-out.

For now, I will probably stick with AMG, and hope the LiFePo4's drop a little in price, and more real world use information is released. What we don't have yet, is enough reports on high voltage systems and range performance data. Tthe 24 and 36 volt packs are out there and working, but not without some hurdles. We also do not have many reports on LiFePo4 users that just "plug and play" the batteries. Right now the LiFePo4 user majority are well educated and knowledgable. I am not sure LiFePo4 packs are ready for the naive consumer.

Hey Thanks again!.


so, question, how do you know the D&D has more power? Just because one website says? I still have yet to see a torque curve to verify that claim.

As far as batteries, I don't know yet... I got some free gels, I'll do LiFePo later.

The issue with lifepo is that while you may get 60Ah batteries, string them together for 72V.... some of them are really "soft" and can't discharge continuous what people want to get out of them. Their discharge rating isn't that of lead, so its hard to compare the two. Charge rates might be higher, but instantanious current carrying capability is lower with alot of the lifepo's. Some of them, like A123, have different chemistries that help... and couple that with the fact that you're paralleling many together.


I have no idea if the motor has more power or not. I am taking the dealer for their word. It is however a longer body, having longer windings and longer armature must be worth something. I spoke with D&D directly, and they mentioned a spec sheet. I will see if I can get that, now that I have taken delivery of a motor, they may be willing to give that info up.

Lifepo4 "soft"
I think the Thundersky and Cloud EV offerings are a step in the direction to not be "soft".
It seems these are the quickest discharge rate capable offering so far. I am actually leaning toward ordering the Cloud EV Lifepo's. I cannot really afford them, but I could sell off some of the other toys to finance them. The only hurdle I am trying to get over is the internal personal struggle of knowing a year from now $5000. batteries may cost $3000. etc. That's the Swamp Yankee blood in me.... in other words: CHEAP! :>D

I am however liking the idea of nearly double the range, and 100 lbs lighter pack weight. That will bring the bike under the factory wet weight by almost 30 lbs.



any more updates? I'm hungry for some more :)

I wish I could just have my blog show up here as a blog.

I'll just have to start one.

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