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Real torque value for cheap chinese motors

I14R10

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I've been searching online stores for DC motors with gearbox, rpm around 100. I've come across cheap chinese motors priced around 7-12 dollars. Specifically this one https://www.aliexpress.com/item/32701965322.html . It will be used for remote controlled car, with one of these motors for each wheel, so nothing important that needs to be very reliable.

They claim the torque for 167rpm model is about 6kg cm and up to 16kg cm for stall torque. But it ranges quite a lot for different sellers (but for the same looking motor). Some say 7kgcm, some 9kgcm... And also the price is different for same looking motor.
So my question is - is there really a difference in these motors from different sellers - that some seller sells same type of motor but with higher torque than other one? Or is it the same mass produced motor, but their measurements of torque are wrong?

Here's the chart from one of the sellers
HTB1_22Te8iE3KVjSZFMq6zQhVXa9.jpg


And additional question, can you recommend me any store that sells low rpm high torque dc motors, but with not-insane prices? I've seen same type of motors as these chinese selling for 85-100 dollars...
 
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BradtheRad

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Specs are easily faked of course. No one can assure you as to a vendor's reputability. Price is not a reliable indicator. You can try a Sherlock Holmes approach by looking at customer feedback. Did anyone use the motor for a similar purpose as you?

same looking motor

Looking at your table it suggests there are various gearboxes but only two motors. Notice the 12V motor has Ampere figures that are the same down the column (no load A, rated A, stall A). And the 24V motor has its Ampere figures unchanging down the column.

Whatever you purchase this time, expect that you'll want to try other gear ratios later. Suppose a vendor makes you buy a motor with each gearbox -- how many unneeded motors could you end up with? Does any vendor offer a plain motor, with the option to attach various gearboxes?
 

KlausST

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Hi,

a motor for a car. Who cares about 6kgcm or 16kgcm?
Did you calculate which torque your car really needs? For how long time?

What is the torque used for? For acceleration only? For high speed? To pull something?

Klaus
 

I14R10

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Hi,

a motor for a car. Who cares about 6kgcm or 16kgcm?
Did you calculate which torque your car really needs? For how long time?

What is the torque used for? For acceleration only? For high speed? To pull something?

Klaus

I'm not sure exactly how much torque I need, but it's just around 8-12 kgcm. It needs to be used for low speeds.
--- Updated ---

Whatever you purchase this time, expect that you'll want to try other gear ratios later. Suppose a vendor makes you buy a motor with each gearbox -- how many unneeded motors could you end up with? Does any vendor offer a plain motor, with the option to attach various gearboxes?

I can eliminate certain rpm-s (below 30 and above 300) so that's only a couple left.
And yes, I can buy this motor on its own but not the gearbox, it seems.
 

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