Easy DIY Electric Motorcycle Conversion

We started with a Honda Rebel junker and a dream - to make a practical, zero emissions vehicle for commuting in San Francisco. After consulting with some plans available online which required chopping the frame significantly, We decided to figure it out for ourselves. Armed with a basic metal shop, we methodically convert the Honda rebel 250 into a clean quiet bike in about a week. It is registered and insured in CA as a modified 250. (if the power system were 24V or less, no registration is required).

The old rebel rolling chassis provided us with many of the needed parts - wheels, tires, brakes, etc... which was a real bonus - but it also supplied us with many rusty, broken, stripped or missing parts. In fact, most of our difficulties were because of the old parts, not because of the conversion itself. Without these annoyances, the conversion would have taken about two and a half days.

With an onboard 48V charger and 3-prong wall plug hardwired on, recharging is easy anywhere there's a wall outlet. Charging time depends upon how depleted the batteries are, but usually they were topped off after 5-8 hours.

Step 1 Gather Parts, Tools and Materials

We scored a blown Honda Rebel 250 on Craigslist for under $500. It had a blown engine, but included all the other parts needed to make the bike safe and street legal: Lights, brakes, wheels, shocks, etc... I had a set of 4 deep cycle batteries from previous projects. We purchased most of the other AC components from Electric Motorsport in Oakland and also consulted a set of plans from 21 Wheels. Ultimately we had to redesign many aspects of the project and develop our own solutions.

BASIC PARTS LIST
Honda Rebel 250 rolling chassis
Perm PMG-132 electric motor
(4) 12V 50Ah batteries in series
36V-72V PWM controller
5 k potentiometer (i.e. twist grip throttle)
48V AC charger
48 -12V down converter OR additional small 12V battery (for lights, signal and horn)
#4 welding cable and lugs
Custom sprockets

BASIC TOOLS
Welder
4" angle grinder (with cutting and grinding wheels)
Drill press
Metal band saw
Sawzall
Standard auto shop tools, wrenches
Heavy duty wire cutters / crimping tool

RESOURCES
Honda Rebel service manual
Make Magazine Gear calculator (for choosing sprocket sizes)
EL Chopper ET builder's plans - outdated, but a great starting point
Friends who can help

Comments

[TheMadScientist]

i'd like to note (this instructable is a bit old but still meaningful) that if you're to do this conversion, you have to find motorcycle that uses chain drive. using a belt drive motorcycle will result in not being able to adjust the chain tension as it stretches, prematurely wearing out your chain and sprockets.

[Calorie]

The zip wraps do concern me. During a wreck the plastic will stretch and break the locking tabs on the zip ties. I pick through wrecked cars at junk yards, and I've seen batteries where they shouldn't be.

[sparkyrust]

That's a good concern, and one I considered. Ultimately I weighed all the aspects of those zipties vs. metal, which I had in the original design. The weight savings is huge, the ties are remarkably strong, and the batteries are wedged in so tight, with lots of thick battery cabling too boot, that they don't come out easily, even when I want them out. And with a top speed of about 35-40 mph, if I'm in a wreck that has enough force to knock those batteries out of whack.... well then I've probably got a lot of problems to deal with. Thanks again for the comments, Best.

[Calorie]

That's true. Your going to have problems at 40 mph. But it's best to minimize them. Remeber the important equation is:

Force = Mass + Acceleration

The best way to think of it is that a static force has no change in acceleration. But even a slight difference in acceleration leads to a huge change in force. You can hang on a tree with shoe strings, but the moment you try to swing into the local swimmin' hole you'll find yourself in a great deal of pain.

That change in acceleration is the important part. That's why bicycle and motor helmets seem hard, but in reality they slightly slow the rate of acceleration.

Just being a math and safety dork all at once. I've cracked three helmets with nary a car in sight. All my fault :-(

[ironman0104]

Force = Mass X Acceleration.

[nickstou]

... um.. mr. math and safety dork (i am a bit of one myself)...

force = mass "X" acceleration...

maybe hop off your soapbox and check your formulas...

-CW

[raju4love]

hey its a good job done by you
i need some help from you because you are a expert
please do me some help
i want some knowledge about this so please contact me at my mail id please

[e-mail]


pls please do me this help please please

[PTooTi]

Wahhh! I used to have a Rebel hard to believe it was almost 25 years ago nice little bike and the conversion looks kool too how fast/far can you travel on it?

[nepemex]

great job i wish yo can put more instructions about how connect the controller and the engine, and whta happen with the Throttle?(how it will work ?)
as well as WHAT HAPPEN WITH THE BRAKES?
in resume :can you put a BLOG and a STEP by STEP method?
(under our own risk)
thanks! great job

[deepsea5]

sparkyrust; thanks for posting this!

For those who have done this conversion: have you tried the Optima Blue Top battery; and converting headlamp/tail lamp/directional lamps to LED bulbs?

[Bosun Rick]

Has anyone considered using a HYDRAULIC (think Hydrostatic) drive with an Electric motor?

No drive alignment issues, just hoses, a pump and the Hydro motor

See www.hydraulicinnovations.com for details. Their unit is larger and heavier duty than this project would require, but the concept would be the same.

[BruceKenobi]

Hi! I liked the instructable a lot as I am researching to embark in a similar adventure; however I found something contradicting: you mention in the parts list that you used a "Perm PMG-132 electric motor" and then mention "We purchased most of the other AC components from Electric Motorsport " but the Perm PMG-132 is a DC motor (I checked!) it is the Perm's edition of the E-Tek, both are DC motors, so you are doing a DC conversion, what AC parts did you need? just asking as I have been researching a lot on the AC vs DC motor debate and your instructable was a good "case-study" for a success story!

[astonehouse]

Hey guys here is just a little comment to think about. Hydrogen has been the "fuel of the future" for 45 years. And always will be. Forget your hydrogen powered whatever. There is no feasible way to, A; Compress the hydrogen enough to get a reasonable energy return per fill up, and B: no way to completely seal up any container of hydrogen. Tiny slippery little molecules just will not stay in the jar.And C: Anyone remember Lakehurst Field and the Hindenburg? A pleasant fantasy, a car the just makes water when you drive. Time to wake up now

[LingCullen]

Hindenburg disaster was not caused by hydrogen. The myth that it was has been tackled and disproven many times over. It was a combination of the chemica treatment it got and the aluminium covering. If hydrogen was burning in the video, we would not have seen the flames and smoke that we did. The hydrogen can be seen burning after the fact, but that was long after the accelerated due to the chemical treatment on the blimp.

[snelpiller]

Im wondering whatever happened to Hondas car Clarity that ran on hydrogen :P

[XOIIO]

Man, you gotta psot a video going 0 to top speed, that bikle looks sick

[balun]

great work....

[rc jedi]

i fly r/c planes, the prices of lipo batteries has come down dramatically. I
get mine from china.
http://www.hobbyking.com/hobbyking/store/uh_listCategoriesAndProducts.asp?catname=20C+Discharge&idCategory=239&ParentCat=85
i fly 24 volt brushless motor setups, these batteries can offer much greater power to weight ratio. They do require special chargers and cannot be discharged below 3 volts per cell. but lead acid shouldn't be deep cycled either. just an option.
i always use paypal, especially overseas orders.

[eron silva]

Dear friends, is it possible to use a car dynamo (without the AC converting part) as an electric motor for a bycicle conversion?
* I could get a used one almost for free;
* a car dynamo weights 12 kg, but some of it could be shaved off (unnecessary handles, installation arms, perhaps - maybe a half kilo or more...).

[Danish M1Garand]

Look for a DC motor Treadmill. These have a fairly strong DC motor. You can find these on the curb on trash day that have little or no use on them.

[eron silva]

Friends... I got the answer by myself @ www.4qd.co.uk/serv/appnotes/dynamo.html . Problem is, the article brings the sobering words "the cheapest way is not always the simplest". Check it out and count your blessings if you can afford US$500 for an etek motor, and what-not for the batteries... I will keep on looking for a cheap solution! Any suggestions are welcome (my requirements are humble: 50 Km/h, 24 km round trips, mostly level terrain) 

 

[criddifer]

you could put a car altanator with a toothed gear on the shaft with very little friction to turn it to charge the extra battery for the light and other normal eletronics on the bike and it should work

[Danish M1Garand]

It will add only drag to the system. You can capture some energy through regenerative braking. You add a lot of complexity to your system though.

[Hubiewan]

Hubiewan asks:
Why not use the original gas tank to store the electronics, thus keeping it looking like a regular bike?

[abadfart]

i agree because then you could fit the other batteries up front and then you could have real side bags for runs to the store and could store the charging cord in the gas flap

[VampiricPie]

I want people to look at mine and say, "That's not a regular bike." Therefore, when I make my ebike, the design is going to be based on the components it uses, which is how the design of gasoline motorcycles arose.

[anjimehra]

Hi
Whatll be a good ratio for a bike weighing app. 120 kgs + a 70 kg rider?
Anji

[bennelson]

I built a similar project last summer. You can see my basic web page about it at Ben's Electric Motorcycle

Mine kept the gas tank for looks, and it works as a cover for the charger.

Great job on yours Sparkyrust!

[vistal]

Heres the thing about electric.In the wrong hands it more dangerous to the environment. People will not recycle batterys but toss them in landfills. Electric is only good in the hands of private builders like you and me . People who know where to take them/use them and recharge them Right. It not worth the money to invest in electric bikes/cars till we get better Battery cells which can produce the power we need to make the vehicles run a longer distance at leat 250 miles.Hydrogen is the wave of the future.

[sojakai]

I have a friend who loves going to the landfills and getting the car batteries that people leave. Puts them on a desulfator and brings them back to life. He gets a truly dead battery from time to time, but its pretty rare.

[cantthinkof bettername]

Cool video. How much did it cost, and what is the range and charge time?

[Stryker]

I also have a Ben's Electric Motorcycle

BEM

[sparkyrust]

The guys at Electric Motorsport in Oakland have a few bike designs that use the gas cap on the tank as a cover for the charger too. It's a ironic twist that is always good for a chuckle. Thanks for the Comments. Cheers!

[alex-sharetskiy]

you wouldn't power your toaster on gasoline, would you?

great argument!

[jongscx]

...I would. I already do my blender that way...

[alex-sharetskiy]

well, i don't like my toast to smell like gasoline...

[JTurner385]

Is it possible to get all of the needed parts for the conversion from a used 48v golf cart? The thing is, I am in Mexico and the sources for most of the parts are in the US. I can have them shipped but it does cost a lot and i am worried about customs fees. Any suggestions?

[alloqba]

Hello! First of all - awesome conversion, although I would have left the gas tank just to look nicer :) Next - I have a question about battery: After half a year of using this moto - do you see drastically battery life shortening? Are they just standard ones - used for cars, or some kind of deep-cycle or else? Finally - how can you compare acceleration of this motorcycle to others 250cc or 125cc gasoline motorcycles? And how comfortable it is to commute in town using this vehicle? (I mean - if you are continuously overtaken by other cars, or you are just "normal" user of the street)

[Uncle Kudzu]

i wonder if something like that NuVinci CVP hub would increase efficiency on a project like this, or is the simplicity of just two sprockets an advantage in some way?

[Arayas]

Hey guys looks it turned out really good -excellent project! I've been considering converting a bike for my senior project. Any chance you could post a rough estimation of the costs? Also, I would love any info you could provide on where one might be able to look up / purchase the batteries...? Congratulations again and thanks in advance! -Ian