Radium 6485 & 6455 Motors

Not for a given voltage. Horsepower = torque x rpm. So if you increase rpm you get free horsepower (although there are more losses and eventually a limit is reached where heat becomes excessive). This is why F1 engines were running at 20k rpm before the FIA limited the max rpm allowed to stop skyrocketing development costs

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Engines does not equal electric motors.

Anyway, Im no motor Genie but I know abit since its pretty close to my field. Mostly quoting Vedder tho. Might have mixed up how voltage relates to rpm.

"KV

First of all, I will try to make some things clear about the KV rating of these motors. Even if there are several versions of the same motor available with different KV, the properties of the motor are exactly the same but at different voltages/currents. The only difference the KV makes is how to choose an ESC and a battery pack, but I will explain more about that in the ESC section. For the same motor, the low KV versions have more windings with thinner wire, while the high KV versions have less windings with thicker wire. As long as they have the same mass of copper, they are exactly the same in regard to max power output, torque, efficiency, max RPM; but at different currents/voltages. If they don’t have the same mass of copper they are different, but it is always true that the more copper is squeezed into the stator, the better the motor is."

(Chosing the right BLDC motor and battery setup for an electric skateboard | Benjamin's robotics)

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Yes you are talking about different kv and voltages but the same rpm so in this case that’s right it doesn’t matter, if the rpm is the same then the power is virtually the same no matter the kv provided the copper mass is the same. Sorry I thought you meant different kv but same voltage before.

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Bit of extra work that wasn’t anticipated so sorry for the delay on this latest batch!

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You switched to the good bullets! :open_mouth:

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On this batch we upgraded to a much higher quality enamel coating on the wires thats also rated for 40C higher temperature.

However this then caused the varnish that coats the coils to behave differently resulting in a coating that was so thin you could pull some of the coils off with your fingers. So I have had to disassemble this batch and coat each stator in a special epoxy by hand.

Before and after adding additional coating to prevent winding failures:

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Proper QC :ok_hand:

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What epoxy is that?

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I love that the sensors are in the base :ok_hand:

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Moving them there solved the sensor noise issues, and then I went through 4 different hall sensors and supporting component configurations to get the hall sensors running perfectly with vesc… Who knew vescs would be so fussy🙄

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All of us haha

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I’d like to affirm things that have already been reported for the reacher 6485s. They run hot. Like 15C hotter than my fs6384s. Granted my cruise speed is at like 6400rpm.

Would be good to compare them on the same set up

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sounds good. You have my address, I’m expecting a free set of 173kv reachers :rofl:

I lost your address…imagine that

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A scientific test would be good. I know Hoyt is working on an esk8 dyno. Would be cool to test all of our common 638x motors. Maytech, flipsky, freerchobby, reacher, KDE, etc.

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Is this still in the plans for the next batch? :upside_down_face:

Change of plans now… We’re no longer keen on doing the shaft upgrade we had planned as MOQ is 200 pieces and we don’t expect to sell that many unfortunately

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So the batch in stock right now is 45mm or 30mm shaft?

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