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Hi Hunter

What I'm missing:

Brakes
4x Wheels
Transmission gear
Transmission chain
Steering wheel
Rear wheel Axle
Front wheel axle
Chassis
Seat
Control Panel


What you do is you get a go kart with all of the above bits - but with a broken engine or a good one and sell the engine

Keep an eye out on e-bay or local papers -

So it seems like i need to find a 5000 watt DC motor...AHH!
Would 1000 watts of output be sufficient?


1000 watts = 1kw, would be sufficient to have a small amount of fun
5000 watts = 5kw, would be enough for a whole lot of fun

Best to start small and cheap -
 

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1000 watts = 1kw, would be sufficient to have a small amount of fun
5000 watts = 5kw, would be enough for a whole lot of fun

Best to start small and cheap -
The motor on my tractor is only 3hp.
It ripped the transmission apart so you need to be careful of torque. Again, we'll cover that later on.

I would second the option of buying a working, rolling kart with or without ICE and convert from there. That saves you making up a load of safety related stuff that you don't understand yet and could leave you injured, or worse, injuring someone else.

Bear in mind that this is a forum offering help and support to those working on the electric element of an EV. If you need to know about 'How do brakes work?' and 'How does steering work?' then you need to find a different forum for that level of support alongside this one.

Also, you mentioned studying mechanics next year.
I'll say this one last time, read, read, read. You need to get reading more books, forget the internet, nothing beats a good old text book. If you are into making things and into cars then you should have been reading everything, magazines, picture books, text books, 'How To...' books, Haynes manuals, anything and everything to do with your interest.
By your age (and I am nearly three times your age) I had best part of 300 books on cars, trucks, engines, mechanics and passed motor vehicle tech exams with 100% on all the papers.
Nothing beats reading until you can get your hands dirty and then nothing beats experience, but that takes time to acquire.

You will need to be a little more proactive in your learning too. People here will get quickly fed up with the spoon feeding of every little bit of information.

Oh, one last thing. In that 'shopping list' you missed out the most important component of an EV, the controller.

Homework:
With your 24V 500W motor and 24V 12ah lead acid batteries what would be your run time at maximum power and 50% depth of discharge?
:)
 

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Discussion Starter · #43 · (Edited)
500watts / 24volts = 20 amps. Batteries provide 24amps-hour (not counting any losses) so a little over an hour? with the count of depth of discharge...1 hour or below?

The motor comes with a controller, motor, and throttle.
Is 500 watts the max output, or if i provide more voltage/amps is there higher output? Or would the controller stop an exceed of 500 watts?
such as: 48V * 20A = 960 watts
 

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Missed the controller in the kit, sorry.

You don't have 24Ah, only 12Ah.
There are two batteries, 12V and 12Ah each.
Put them in series and you will get 24V but only 12Ah.
Put them in parallel and you will get 12V but 24Ah.

So your motor drawing 20A will flatten the batteries completly in a shade over half and hour. Allow only 50% depth of discharge (DoD) and that is then reduced to around 15 minutes.
:)

The charger is 12V at 4A and so it would take 3 hours to recharge each of the batteries in turn so you have a 6 hour recharge time from flat, or 1.5 hours each if you have only used 50% DoD.
 

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Discussion Starter · #45 ·
Missed the controller in the kit, sorry.

You don't have 24Ah, only 12Ah.
There are two batteries, 12V and 12Ah each.
Put them in series and you will get 24V but only 12Ah.
Put them in parallel and you will get 12V but 24Ah.

So your motor drawing 20A will flatten the batteries completly in a shade over half and hour. Allow only 50% depth of discharge (DoD) and that is then reduced to around 15 minutes.
:)

The charger is 12V at 4A and so it would take 3 hours to recharge each of the batteries in turn so you have a 6 hour recharge time from flat, or 1.5 hours each if you have only used 50% DoD.
WOW :(
So im going to need 4 batteries. Two in a series connected by series to the other two which are connected in parallel?

Is 500 watts the max output, or if i provide more voltage/amps is there higher output? Or would the controller stop an exceed of 500 watts?
 

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Hey Hunter, neighbor. I would have never thought it possible that a youngster from Miami would have any kind of technical inclination. Silicon is very popular here though. Boys carry it in their iPhones and girls in their...nevermind.

I'm not sure if you've given up on a real car yet but I'd take a second look. Don't go for a junker special. Buy a car you can drive so you can check the transmission, brakes, steering, etc. Check out Craigslist. But be wary of "excellent" shape claims. I bought a 1996 Cabrio last year and had to do a lot of work on it just to get it ready for a conversion. So much so that I came across another Cabrio in better shape and bought it. Now I have 2 mediocre ICE cars and no EV :mad:

I'm not trying to discourage you from the Go Kart idea; there's a couple of indoor and outdoor tracks in and around Miami where you can ride. There are some really slick and fast electric go karts on YouTube, check them out. But if you're on a budget and just want to get started, I would consider a bike a more utilitarian first EV. You can't ride a Go Kart to the corner store but you can probably get away by riding an electric bike, especially if you leave the pedals in even if they're not connected. Cops have different takes on what constitutes a 'motorized' vehicle but bikes, especially electric ones (ie: no noise), will pass more often than not.

JR
 

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Discussion Starter · #47 ·
Would they get mad at a trike...like two wheels in front and one in the back? I dislike motorcycles cause they more dangerous and i flipped forward once and miraculously nothing happened to be, but i was going on an e-scooter.
 

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Discussion Starter · #49 ·
Is 500 watts the max output, or if i provide more voltage/amps is there higher output? Or would the controller stop an exceed of 500 watts?
 

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From what I undestand, the controller will control, and limit, the power to the motor. The motor will just burn out if it gets too much.

Have a look at the controller forum and, using the search function, read stuff on the Soliton controllers, the Paul and Sabrina Controller, The open Revolt Controller (other name for Paul and Sabrina's work), and any other interesting threads.
 

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Discussion Starter · #51 ·
Do you guys thing an axial motor with neodymium magnets would be strong enough to move a go cart? maybe even a car?
 

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Do you guys thing an axial motor with neodymium magnets would be strong enough to move a go cart? maybe even a car?
Depends on the motor.
The bigger ones should be able to but the little tiny ones wouldn't.

What sort did you have in mind?
 
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2 and 4. Why on earth would you use standard car batteries? You will kill them in no time and will have wasted your time and money. No capacity compared to deep cycle golf cart type batteries. Do it right from the start.

Pete :)
 

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How many standard car batteries would i need to achieve 400 amps at 24V - 48V?
You would need two, three or four standard car batteries to achieve 24, 36 or 48V. Just about all standard car batteries will give you 400A, for about 5 seconds, three or four times a day for a year or two. Just about perfect for starting an ICE car at 12V.

2 and 4. Why on earth would you use standard car batteries? You will kill them in no time and will have wasted your time and money. No capacity compared to deep cycle golf cart type batteries. Do it right from the start.

Pete :)
You need to pick and chose what sort of battery you need depending on the useage. Standard car batteries are perfect for starting ICE cars but useless for running an EV.
 
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If he is talking about starting batteries for his ICE he is in the wrong place and its not that hard to figure out. 12 + 12 = 24 or 12 + 12 + 12 + 12 = 48. Not sure why that one was asked. I must assume by the voltage requirements he is talking EV and not ICE starting. I know most starting batteries can belt out a whopping amount of amps but not for long. So the amp part is pretty moot.

The question was pretty open ended and pretty vague and nothing about the application.
 

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Hunter is young and trying to learn about EVs. He hasn't got as far as batteries yet so, just as I was when I first thought about it, a car battery seemed a good place to start. Oh how wrong I was.
He'll learn, gradually, as he asks questions and we respond to them.

Hunter, have you bought that Bob Brant book yet?;)
 
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True but he can read and search like I did. I always try that first then come back after a good search and read. Usually the question is answered quickly before I have to ask. Reading gets me thinking and that leads to questions then a search to see if the answer is already there. Yup, usually is. It is good stimulating fun and a nice self paced course in all sorts of things. Math, physics, electronics, mechanics, and much more.

I'd say what do you think? and what have you found out so far? Bet he already has the answer but may not realize it.

It helps the teacher know what a student knows. Most know way more than they give themselves credit.
 
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