Electric Motorcycle conversion

[LetsBolt]

Ok, thanks Ben. That puts my mind at ease. Any vehicle I couldn't ride in the rain would be pretty useless down here in the summer.

So have you considered using a brushless motor in an electric motorcycle? Sounds like it would be even lower maintenance than the ETEK you are using...'course finding a controller that would work with a brushless motor could get pricey...

[bennelson]

This project was the first time I have done ANYTHING like this. I was going for simple and inexpensive.

A motorcycle could be designed with a brushless motor, very fancy battery packs, and regenerative braking.

The best part about a system like this is that it's all modular. If I wanted to, it would be easy to change out a motor or controller, or upgrade to a much more expensive battery pack.

[chrisp68]

Ben,
Thanks for the information... the bike looks great. I'm going to complete a conversion on a Honda CB400 (1980). The gas engine ran about five years ago when I was given the bike however it has just sat around. I don’t feel like putting a lot of money into an ICE to get it running. It will need all kinds of cleaning and a new muffler package. Instead I want to run it on electricity. Anyway, I’m going to see if I can sell the engine and use the profit to purchase batteries and an electric motor. My question to you is, do you have a wiring diagram for you motorcycle? It sounds like I can almost duplicate what you have done. The only other thing I want to do is charge the batteries via solar panels to be completely free of fossil fuels.
Any help is appreciated!!!

Thanks,

Chris

[bennelson]

Hey Chris,

I used the diagrams from Alltrax's web page. They are all available as PDF files you can download. The PM Motor diagram is what most closely follows what I did.

See them at:
Document Depot


I also just talked to a guy today who stopped by who is converting a 79 Harley Sportster to electric. I showed him how I had mine rigged up.


Take care,

-Ben

[chrisp68]

Ben,
A few more questions...

1. Why the expensive batteries? ($160 EACH for 4 Optima yellow top 55AH batteries) Will a standard 12V car battery not work?

2. On the ALLTRAX AXE - PM wire diagram, what is the purpose of the Main Contactor?

3. Also on the diagram, where would the DC to DC converter be placed?

4. Would it be possible to salvage old parts from a golf car? (Example: the throttle mechanism)

5. What is the current draw for the 48Volts battery pack when charging? I want to size my solar panels properly for charging purposes.


Sorry for simple questions... I have a better mechanical background than electrical.


Thanks,
Chris

[bennelson]

Those are all great questions

Originally Posted by chrisp68

Ben,
A few more questions...

1. Why the expensive batteries? ($160 EACH for 4 Optima yellow top 55AH batteries) Will a standard 12V car battery not work?

The batteries are where I splurged. They are spill-proof and can pull a lot of power very quickly. Great for acceleration.
12V car batteries would be a poor choice, they are designed for high power, but only briefly. They are not designed to be drained mostly empty repeated times. Another alternative would be either AGMs (absorbed glass matt) which the Optimas are basically just a fancy version of, or deep cycle boat batteries, which are cheap and hold a fair amount of power, but require watering and could spill.

Originally Posted by chrisp68

2. On the ALLTRAX AXE - PM wire diagram, what is the purpose of the Main Contactor?

The main contactor interrupts the high power circuit of the batteries, motor, and controller. It is usually used as a security feature - you need the ignition key to make the contactor go - and as a safety feature. If there is ever a bad situation where the controller freaks out into the "full on" mode, you can turn off the contactor to kill power to the motor. Since many electric motorcycles have a direct link between the motor and rear wheel, you need the contactor as an electrical disconnect.

The earlier version of my motorcycle didn't have a contactor on it, just a cut-off key. It worked fine like that.

Originally Posted by chrisp68

3. Also on the diagram, where would the DC to DC converter be placed?

Wire up the DC/DC converter so that it turns on when you put your key to the accessory position. This will be a totally seperate circuit using smaller, lower power wires than the motor and main batteries use.
Connect the DC/DC converter to either end of the main battery pack. If you batteries have two sets of posts (one set on top, other on the side, etc) hook up the main power cables to the big posts and the DC/DC converter, charger, or anything else that goes on there to the other set of posts.

Originally Posted by chrisp68

4. Would it be possible to salvage old parts from a golf car? (Example: the throttle mechanism)

Yep, an electric motorcycle is very much golf cart technology. In fact, a decent place to order parts from would be an electric golf cart place.

Originally Posted by chrisp68

5. What is the current draw for the 48Volts battery pack when charging? I want to size my solar panels properly for charging purposes.

Using a KILLAWATT, the power usage at the wall is about 110 watts. How many watts are used depends on the power of the charger. Higher amperage chargers charge faster, but also cost more.
A typical rule of thumb is to charge at a rate no faster than 1/10th the total amp-hours of the battery. Since my batteries are 55 amphours, I shouldn't use a charger faster than about 5 amps. Optimas are actually better that way that they CAN take a faster charge, but lets not get to crazy here. When I put a 6 amp/12volt charger onto a single yellow-top, it does get slightly warm while charging.

Originally Posted by chrisp68

Sorry for simple questions... I have a better mechanical background than electrical.

Thanks,
Chris

That's OK, I have no idea what I got myself into doing a project like this.
So far, this project has inspired or spawned at LEAST three other people to convert cycles to electric.

Take care,

-Ben

[bennelson]

Just got a volt-meter in the mail today for the cycle. It was only $5 through Electric Vehicles, USA.

Electric Vehicles USA, Inc

Yep, it's analog and doesn't have any actual volt markings on it. It's perfect!
Just throw it into the tachometer housing and I can finally check my state of charge at a glance.

(Yes, I still have a digital multi-meter for testing and troubleshooting, but I wanted something I could bolt to the cycle and leave there!)

[LostCause]

Originally Posted by bennelson

Yes, the motorcycle can be ridden in the rain, as was demonstrated this past Sunday at the MREA Energy Fair by fellow Ecomodder, Ryland.

Congratulations on all your exposure.

As far as electrical shocks go, electric vehicles are different from mains lines. You get shocked from an outlet because the earth acts as a ground...your body merely connecting the circuit. An electric vehicle generally is closed loop, meaning you could submerge the thing in fresh water and not kill yourself.

Ofcourse, the use of fuses and contactors as backup is always a smart thing. Prudence = longevity...

Originally Posted by www.EVdrive.com

Water crossings

There are riders wondering about what happens when you cross a creek with the electric bike. Streams are generally low salt content. These motors will actually run under water, not that it would be good for the motor, but the water is not involved if current does not flow in it. Any current that does flow is localized inside the motor compartment and chassis. It would NOT go around and kill fish in the steam, and it would not shock you if you are standing in water hanging onto the metal bars. The currents stay locally inside, positive terminal post to negative terminal post.

This is very unlike the AC power grid where power is relative to earth and wants to find any conductive path to ground, including through a person strongly coupled to the earth standing in water...

- LostCause

[MetroMPG]

Originally Posted by bennelson

Just got a volt-meter in the mail today for the cycle. It was only $5 through Electric Vehicles, USA.

That's a great price! 8-18 volts spec - I take it you'll just monitor one batt. Once you've got it "calibrated" it'll be helpful for sure.

I don't know about your Optimas, but floodies must be kept above a miniumum voltage under load to prevent damage. I'd say some kind of voltage indicator should be on every EV.

[chrisp68]

Ben,
Do you know of a good web site for new or used motorcycle parts? I have to update a few things other then the engine to get the cycle road ready, specifically for a Honda CM400T 1980.

Thanks,
Chris