# Help on electric go cart.



## Ehgemus (May 4, 2008)

Hello I am new to this forum and to EV. I just purchased a used go cart, racing type frame. I am thanking about making it electric power. I need help on the motor part. I thought about a 24v system because I can fit two car size battery on the cart and possibly three if I had to. So what type of motor would you suggest? Thanks for any help.


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## Dennis (Feb 25, 2008)

It just so happens that I have an electric go kart. If you want something to play with, then the bare minimum I would go with is 48 volts. But for serious fun I suggest 72 to 96 volts. The motor I use is an Advance DC A00-4009 series-wound motor chain driven setup with a 4:1 ratio giving me a top speed of about 45 MPH with 72 volt setup. I did try 3:1 but I was uncomfortable with the brakes not working so well as they began to smoke and the stopping power was really starting to diminish as well!

The controller I use is the AXE7234 that is completely programmable and is what I suggest you use for this project. Don't use car batteries as they will be ruined in short order since they are meant for starting and therefore will have thin lead plates that will deteriorate quickly under severe discharge cycles. For this project of yours you need to use deep cycle batteries such as Yellow Optima tops or some cheap wheelchair batteries which is what I use.

There is a member on here called Wirecutter who can definitely give you some pointers on this project as well.


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## ww321q (Mar 28, 2008)

How much are you willing to spend ? If you are patient you can get good deals on ebay and other places on used motors and controllers J.W.


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## Ehgemus (May 4, 2008)

Dennis said:


> It just so happens that I have an electric go kart. If you want something to play with, then the bare minimum I would go with is 48 volts. But for serious fun I suggest 72 to 96 volts. The motor I use is an Advance DC A00-4009 series-wound motor chain driven setup with a 4:1 ratio giving me a top speed of about 45 MPH with 72 volt setup. I did try 3:1 but I was uncomfortable with the brakes not working so well as they began to smoke and the stopping power was really starting to diminish as well!
> 
> The controller I use is the AXE7234 that is completely programmable and is what I suggest you use for this project. Don't use car batteries as they will be ruined in short order since they are meant for starting and therefore will have thin lead plates that will deteriorate quickly under severe discharge cycles. For this project of yours you need to use deep cycle batteries such as Yellow Optima tops or some cheap wheelchair batteries which is what I use.
> 
> There is a member on here called Wirecutter who can definitely give you some pointers on this project as well.


Thanks Dennis for some ideas on the motor and controller I will look into them, do you have any link for these items? I will be using deep cycle batteries, I just mentioned car size batteries as to size reference. I should have been more clear on that. also do you have pictures of your cart?


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## Ehgemus (May 4, 2008)

ww321q said:


> How much are you willing to spend ? If you are patient you can get good deals on ebay and other places on used motors and controllers J.W.


Thanks I have been watching ebay for some parts but I am still trying to figure out how all this stuff works and what I need to buy.


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## Dennis (Feb 25, 2008)

I bought all the electrical stuff from electricvehiclesusa.com except my 72 volt to 48 volt step down power supply for my contactor which I designed myself. I would try your local Craiglist first or Ebay to save on some money. I spent way too much on the motor and controller that I should have otherwise found by my local Craiglist or Ebay.


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## Ehgemus (May 4, 2008)

Dennis said:


> I bought all the electrical stuff from electricvehiclesusa.com except my 72 volt to 48 volt step down power supply for my contactor which I designed myself. I would try your local Craiglist first or Ebay to save on some money. I spent way too much on the motor and controller that I should have otherwise found by my local Craiglist or Ebay.


I can't afford 400-600 on a motor


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## frodus (Apr 12, 2008)

Ehgemus said:


> I can't afford 400-600 on a motor


if you can't afford that for a motor, maybe you should look at total budget and decide if converting to electric is actually affordable for you.

You might be able to get a forklift motor for under 300, and then get a controller for ~100, then there's batteries, contactor, charger....


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## Wirecutter (Jul 26, 2007)

Ehgemus said:


> also do you have pictures of your cart?


 I can't believe I missed this thread! Well, _I_ have photos of the kart. This is before the motor, controller, or batteries were installed.


















Sorry, I couldn't resist. 

-Mark


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## Wirecutter (Jul 26, 2007)

Having said that, you're probably better off with your frame since I'd guess it's much lighter. You might want to take a much lighter approach - smaller batteries and motor, keep weight down. Check YouTube for username Felixtimlock - that's what he did. Of course, I get an hour versus his 15 minutes of run time, but look at him go!

http://www.youtube.com/watch?v=-C-jdm6sXNI

This is me:
http://www.youtube.com/watch?v=RTdbjXOa-BU

-Mark


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## Ehgemus (May 4, 2008)

Wirecutter said:


> Having said that, you're probably better off with your frame since I'd guess it's much lighter. You might want to take a much lighter approach - smaller batteries and motor, keep weight down. Check YouTube for username Felixtimlock - that's what he did. Of course, I get an hour versus his 15 minutes of run time, but look at him go!
> 
> http://www.youtube.com/watch?v=-C-jdm6sXNI
> 
> ...


Thanks nice go cart and videos. The cart I bought need some work and a few parts, so I will start working on that and than start buying the electrical parts.
So what other parts are needed other than a motor, controller and batteries?


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## Dennis (Feb 25, 2008)

> I can't believe I missed this thread! Well, _I_ have photos of the kart. This is before the motor, controller, or batteries were installed.
> 
> 
> 
> ...



WOW, I cannot remember the last time it looked that good when you built that rolling chassis for me. It has been through some tough times now, Mark. I need to wash it down. Heck the disk brake is almost completely black now, and it has extra battery racks welded on that one of my family members tried to weld perfectly as you did so well and well its not as pretty as what you did with your battery racks. But hey I am now at 72 volts. It's definitely a different experience! I also need to learn how to weld..... so no one else can take her beauty away....


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## Wirecutter (Jul 26, 2007)

Heh, heh. Yeah, I too was surprized at how gunked up my kart gets if I run through a puddle. Those slick tires just splash stuff everywhere. NK2 has been through the wash a few times. I think I've got over 100 hours on it now.

Re: the battery racks... I went through the same thing on the first kart - the black one. The original racks were too small for the Optimas, so I modified them. Yuck - it was ugly. A few weeks back, I cut the battery racks completely off. I did a little rebuilding on the frame last weekend and shot some paint on it. I'm going to put new racks on it and use the same kind of hold down system. I've gotten to like those ratcheting tie-downs.

We really need to get these together some time. Did you implement field weakening on yours? I keep thinking about it, but I haven't done it yet.

-Mark


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## Wirecutter (Jul 26, 2007)

Ehgemus said:


> Thanks nice go cart and videos. The cart I bought need some work and a few parts, so I will start working on that and than start buying the electrical parts.
> So what other parts are needed other than a motor, controller and batteries?


Thanks!

As for other parts - that's where you're ahead of the game. I had to buy wheels, tires, bearings, steering parts, etc, etc. You probably already have all that, and a brake, too. You'll need a throttle pot box for the controller, and the type you get depends on the controller. Many controllers give you the option for different types - potentiometer, hall effect, etc. That'll be under $100. You can make one, and think there was some discussion here about that. There are up and down sides to making your own.

Beyond that, you'll need a couple of switches, some big fat wire, and the mechanical bits to mount motor, batteries, etc. Oh, and a charger (or chargers).

The karts I've made were actually pretty expensive. I was surprized at how quickly the expenses mount for just the parts for a gokart, not counting the EV related stuff. That's why I think you're off to an easier start.

Once you get something on the road, I think you'll find it easier to put time and money into improving it. That's what happened to me...

-Mark


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## Dennis (Feb 25, 2008)

I did try field weakening and gained about 5 or so MPH which to me seems non economical to try to have a permanent implement such as a contactor to engage field weakening as the cost to performance ratio was terrible. So I abandoned the "turbo" project.


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## kixGas (May 2, 2008)

I built one for my 6 year old son as an "intro to EV" project for me. I used a 36 V system with a 1000 watt motor. I used 3 12V (15ah IIRC). It is a little small but it can get him up to 15-18 mph and he has about 45 min - hour of ride time on it before it needs a charge which coincides with his attention span. I built it from scratch (frame steering etc) and I put about $500-$600 into it. Now I am wanting to build one for myself with an E-tek or Perm Motor and get some killer speeds.


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## Wirecutter (Jul 26, 2007)

kixGas said:


> I built one for my 6 year old son as an "intro to EV" project for me. I used a 36 V system with a 1000 watt motor. I used 3 12V (15ah IIRC). It is a little small but it can get him up to 15-18 mph and he has about 45 min - hour of ride time on it before it needs a charge which coincides with his attention span. I built it from scratch (frame steering etc) and I put about $500-$600 into it. Now I am wanting to build one for myself with an E-tek or Perm Motor and get some killer speeds.


Now *that's* what I'm talking about. That's why you want a programmable controller, too, BTW. Make it "age appropriate". However, you spent a lot less than I had to, and the result is as much fun as your son can appreciate. I for one would like to see pictures or even video. (I wouldn't have done what I did if I didn't have a lot of latent kid in me, after all)

On another tack, I'd want to steer you away from the PM stuff. I used a Perm in my second kart, and it burned up after <8 hours of use. Series wound motors are cheaper for a given power rating, and they hold up a lot better. The obvious caveat is that I abuse my karts as much as possible. If you go light and lower power (less than 200 amps) PM motors are ok, otherwise, go for more beef. You won't be sorry.

-Mark


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## Dennis (Feb 25, 2008)

You should show him that picture of what happens to a perm motor when it is pushed hard.  Not so pretty sight to see.


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## frodus (Apr 12, 2008)

here's mine:
http://blog.evfr.net/wp-content/uploads/2008/04/img_1884.jpg

It was originally 72V, has an NEDRA 72V record, 12.1s 1/8 @53.05 mph. I got it from a guy in southern Oregon, Erik Sutton. Great guy.

The motor is an ADC A00 series motor. Only had 24V on it to get it going (saving for batteries), and its pretty fun. I need to put more bats in it and get those slicks on the wheels.

Here's another one that our company, Synkromotive, built, 2 AC controllers, 2 alternators wired as motors, 60V and its a kick in the pants. We keep breaking wheels off of it around turns. Its scary fast.

http://www.evalbum.com/876


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## frodus (Apr 12, 2008)

Wirecutter said:


> On another tack, I'd want to steer you away from the PM stuff. I used a Perm in my second kart, and it burned up after <8 hours of use. Series wound motors are cheaper for a given power rating, and they hold up a lot better. The obvious caveat is that I abuse my karts as much as possible. If you go light and lower power (less than 200 amps) PM motors are ok, otherwise, go for more beef. You won't be sorry.
> 
> -Mark


did you replace your motor with the D&D or ADC yet? I might have a K99 motor available for sale...


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## Wirecutter (Jul 26, 2007)

frodus said:


> did you replace your motor with the D&D or ADC yet? I might have a K99 motor available for sale...


 Here's what happened to the commutator of the Perm PMG-132 when one of the armature windings began to come apart. This failure occurred after less than 8 hours of service behind a 72v 300A controller:










The object on the table at the upper right is the problem. It's a clip that connects two halves of an armature winding together. There are a bunch of them around the perimeter of the armature. When it came loose, it shorted some other windings, and that's what blew out the commutator contacts. (Fluppin piece of shlip.) Perm claims I abused the motor, and I got no love from them. (I wonder what gave them that silly idea? ) To Perm I say, "If you can't run with the big dogs, stay under the porch." ( :nllnn: )

Although this motor would still run, I wasn't going to bet my controller on it. I was lucky - I got $200 for it from a guy that put it into service as a generator.

I replaced it with a D&D model ES-33, and I love it. I've put over 100 very hard hours on the D&D behind the same controller. It's still pretty much good as new. This is the kart as of yesterday:

http://www.youtube.com/watch?v=-pjtjEhPZ7U


Frodus - send me a pm and let me know what you want for the motor. If the price is right, I'm sure I can make a good home for it. 


-Mark


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## kixGas (May 2, 2008)

Wirecutter said:


> Now *that's* what I'm talking about. That's why you want a programmable controller, too, BTW. Make it "age appropriate". However, you spent a lot less than I had to, and the result is as much fun as your son can appreciate. I for one would like to see pictures or even video. (I wouldn't have done what I did if I didn't have a lot of latent kid in me, after all)
> 
> On another tack, I'd want to steer you away from the PM stuff. I used a Perm in my second kart, and it burned up after <8 hours of use. Series wound motors are cheaper for a given power rating, and they hold up a lot better. The obvious caveat is that I abuse my karts as much as possible. If you go light and lower power (less than 200 amps) PM motors are ok, otherwise, go for more beef. You won't be sorry.
> 
> -Mark


Mark-
Thanks for the warning on the Perm motor. They look great on paper but it is nice to see a real world opinion on them.
Here is a video of him riding it a few weeks ago.


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## Wirecutter (Jul 26, 2007)

That's a nice kart. It seems to turn very well - I'm guessing it doesn't have a "live" (solid rear) axle, then? I find that the live axle really lends itself to power sliding, but it's not so hot for tight maneuvering or parallel parking.

That kart has a "high front, squat rear" appearance, doesn't it? It gives it a '60's "retro" look. I like it. Nice work. You are one cool dad. 

-Mark


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## kixGas (May 2, 2008)

Actually it does have a live axle. The motor really bogs down when you turn-especially if I drive it. I have been devising a way to make a low buck differential using freewheels from a BMX bike. I know that there are other ways to accomplish it but where is the fun in that?
The rear tires were actually intended for the front. The original rear tires were go kart slicks about 11" diameter and 8" wide. Those things were so sticky and had such good traction that I couldn't turn. When I would turn the steering wheel the kart would continue to go straight and the front tires would hop around. To remedy that I took the wide tires off, put the fronts on the rear, got new front tires, and placed the batteries in the front. I also did away with the standard go kart 2 tie rod steering system and replicated the steering system used on one of my jeeps with a drag link going from the steering arm to one wheel and a tie rod going from wheel to wheel. This insures that the front wheels are always parallel which give a more precise steering.


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## Alex Everett (Dec 26, 2007)

Ehgemus said:


> I can't afford 400-600 on a motor


Just bought a used golf cart motor for my riding lawn mower project, 48 VDC for $124.00 U.S. including shipping off E-Bay. They are there you just need to keep an eye out for them.

Good hunting.


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