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Discussion Starter · #1 ·
Hello, I’m new here and new to electric vehicles, and electric stuff in general. I’m trying to power a 130 volt dc treadmill motor to make a single rider go kart. I think the motor is rated for 16 amps. I’ve connected a 10000 watt speed controller rated up to 230 volts.
I have tried connecting the motor to a portable car jump starter that has a 120 volt outlet but it doesn’t last long ( even without a load, 10 minutes ) and it can’t supply the motor with sufficient power.

Any ideas of how I could power the go kart, ideally at a low cost. Thank you :)
25821AD6-B29A-4247-A641-0736B92ABDBC.jpeg
 

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Well, you'll need 2 things:

1 - Batteries.

2 - A speed controller of some kind.

Sadly, because your motor is rather high voltage, you'll need a high number of cells. This rules out using any larger cells, because if if they're the right amount of energy, you won't have enough voltage.

To get to 130v, you'll need 130/4.2v = 31 cells in series.

Which means for a gokart you'll need to fit 31 of the same size of lithium battery in the hull. If you were using larger cells, this would take up too much room and weight.

The cheapest cells are used OEM EV cells, but they'll be way too big for you, and too expensive.

Since you're using a treadmill motor, I presume your budget is more like zero, or close to zero, you're hoping for a salvage solution?

Your best bet is probably to go to a tool service center (Dewalt, Makita, etc... there'll be one in every big city where the contractors go), and ask them nicely if you could leave a rubbermaid for them to put faulty lithium batteries in for you to pick up later. Tell them it's for a science project and tell them what it is maybe. They might not be allowed to, but maybe they'll bend rules for you.

Inside tool packs are 18650 cells, about the size of an highlighter cut in half. You'll get 5, 10, or 15 of those in each pack. Probably 1-3 of them will be dead in each pack, but the others should work.

It won't be too hard to get 31 of those. Or, better, 62 of them. They're capable of about 30 amps each, and you'll only need about 10-15 to power the motor at full torque.

Extra batteries added will increase range.

Speed controller can be a real hack if you have zero budget, just power resistors salvaged from stuff or that you make on your own. Not efficient, but free speed control is better than no speed control if you have no budget.

Alternatively, you might be able to get recycled lead acid batteries from an alarm or fire system service company. Those smaller batteries are usually 6 volt, and are on a replacement schedule (every 2 years, 3 years, whatever, and binned regardless of function). It would be huge and heavy, but you could use 21 of those and it would work.

It might be easier just to find and use a lower voltage motor. Motors are cheap and plentiful in scrapyards, batteries are not.
 

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Discussion Starter · #3 ·
Hello, I’m new here and new to electric vehicles, and electric stuff in general. I’m trying to power a 130 volt dc treadmill motor to make a single rider go kart. I think the motor is rated for 16 amps. I’ve connected a 10000 watt speed controller rated up to 230 volts.
I have tried connecting the motor to a portable car jump starter that has a 120 volt outlet but it doesn’t last long ( even without a load, 10 minutes ) and it can’t supply the motor with sufficient power.

Any ideas of how I could power the go kart, ideally at a low cost. Thank you :) View attachment 120737
Well, you'll need 2 things:

1 - Batteries.

2 - A speed controller of some kind.

Sadly, because your motor is rather high voltage, you'll need a high number of cells. This rules out using any larger cells, because if if they're the right amount of energy, you won't have enough voltage.

To get to 130v, you'll need 130/4.2v = 31 cells in series.

Which means for a gokart you'll need to fit 31 of the same size of lithium battery in the hull. If you were using larger cells, this would take up too much room and weight.

The cheapest cells are used OEM EV cells, but they'll be way too big for you, and too expensive.

Since you're using a treadmill motor, I presume your budget is more like zero, or close to zero, you're hoping for a salvage solution?

Your best bet is probably to go to a tool service center (Dewalt, Makita, etc... there'll be one in every big city where the contractors go), and ask them nicely if you could leave a rubbermaid for them to put faulty lithium batteries in for you to pick up later. Tell them it's for a science project and tell them what it is maybe. They might not be allowed to, but maybe they'll bend rules for you.

Inside tool packs are 18650 cells, about the size of an highlighter cut in half. You'll get 5, 10, or 15 of those in each pack. Probably 1-3 of them will be dead in each pack, but the others should work.

It won't be too hard to get 31 of those. Or, better, 62 of them. They're capable of about 30 amps each, and you'll only need about 10-15 to power the motor at full torque.

Extra batteries added will increase range.

Speed controller can be a real hack if you have zero budget, just power resistors salvaged from stuff or that you make on your own. Not efficient, but free speed control is better than no speed control if you have no budget.

Alternatively, you might be able to get recycled lead acid batteries from an alarm or fire system service company. Those smaller batteries are usually 6 volt, and are on a replacement schedule (every 2 years, 3 years, whatever, and binned regardless of function). It would be huge and heavy, but you could use 21 of those and it would work.

It might be easier just to find and use a lower voltage motor. Motors are cheap and plentiful in scrapyards, batteries are not.
thanks for the info. I have two 24 volt motors I salvaged from from some electric scooters. Would those work for a go kart? If so I probably could power them with what I have.
Also is it possible to connect two motors to one speed controller?
 

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thanks for the info. I have two 24 volt motors I salvaged from from some electric scooters. Would those work for a go kart?
Depends on the scooter but, they're probably fairly weak. You might not be satisfied by their performance. But yes.

Also is it possible to connect two motors to one speed controller?
Mmm, possible, yes. To get a result you're happy with... maybe.

If they're identical you might have okay luck. If you put them in parallel they'll each spin as fast as 24v will make them spin, if that's the same speed, then great. Otherwise there'll be a torque difference between sides. Or you could hook them up in series and give them 48v.
 

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From the photo, it looks like you want 120V AC power. You might try a 24 or 48 Volt battery pack with a 3000 Watt pure sine wave inverter.

Check Amazon, or AliExpress for an inverter to match your battery voltage. You should be able to find something for a few hundred dollars. You will lose a bit of battery run time, due to losses in the inverter, but this would be a cheap and easy path.
 
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