Noob question thread! šŸ˜€ ask your questions here!

Thereā€™s an entire metric section :grinning:

:smiley:

:frowning_face:

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Now I remember why I donā€™t shop thereā€¦

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Its FUB converted to metric isnt it?

Is there a good thread or can someone shed some light on motor KV and why the trend seems to be using a higher KV motor and gearing it down vs running a lower KV motor with less gear reduction ?

Like say a 190KV motor, 10s with 15/36 gearing vs 100KV motor, 10s with 28/36 gearing Playing with this calculator http://calc.esk8.it both would have about the same max top speed.

I keep reading about people worried about ERPM limit and a lower KV motor with less gearing keeps further away from the limit.

Looking at specs sheets the lower KV motorā€™s are listed as having more torque and Iā€™d think with the higher tooth count drive gear that it would be less likely to slip as more teeth engaged and surely the higher motor RPM has to incur additional losses from friction and what not.

Is it just a matter of availability of lower KV motors and higher tooth count drive gears ? Is it just because thatā€™s the way itā€™s always been done and easier to follow what you know works ? or is there something else I have missed all together ?

There is a whole thread about motor kv and which to choose it has been tested and 190kv is best for 10s lower the series the higher the kv.

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If you look into e-mtbing a ton of people recommend motors from 130-170kV. Wouldnā€™t say that higher kV is the trend people go.

A lot depends on your needs and your build in general. Also gearing up/down is also limited by wheel diameter. If I think about a 8ā€œ pneumatic wheel I have already clearance issues with 72th wheel pulley. To go more high would make the belt rub on the street :sweat_smile: Same with motor pulley. Below 13th the contact of the belt is just too less.

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Okay I was meant to be asleep an hour ago but just got finished reading both of those topics (would have been done sooner if I didnā€™t have to workā€¦)

Still doesnā€™t really cover off what Iā€™m trying to find. I would probably be surprised if someone has done it but something like a dyno sheet comparing 190KV motor, 10s with 15/36 gearing vs 100KV motor, 10s with 28/36 gearing Theoretically they probably have the same output but my guess is there would be a difference. Like stick a 100kg / 220lb rider on and have them go from a stand still up a slight hill, would the lower KV motor have more punch off the line to mid and the higher KV one have more in the top end ?

The main problem is getting a huge 28 tooth pulley mounted to a wheel. The standard belt spacing determines the tooth size. If you add more teeth, itā€™s not shrinking the teeth to fit the pulley, itā€™s expanding the pulley to accommodate the teeth.

If you order now, as of now. There are still spots available in the March batch

Hey man! When you plug it in to charge, what color light shows?

Just placed my order for the Foxbox Unity!

Another question, is my understanding of the different motor types correct?

  • Belt driven motors This is the standard. It can be a little complicated to work out the drivetrain. Overall is this a safe choice.
  • Hub motors Newer type of motors. Are generally cheaper, but a lot less powerfull than other options.
  • Direct drive motors Newest type of motors. The best, but also the most expensive type. Basically a mix of hub and belt motors, the belt is gone, but the motor is not inside the wheel.

I want to build a pretty stealthy board, so it looks like a normal skateboard if you donā€™t pay attention. Iā€™m planning on using a HAYA board, so the internals will be hidden. To get the stealthy look I have to use direct drive or hub motors, but as I understand it belt driven fits the best. Hub motors are not really powerful enough, and direct drive makes my board over budget (if i use this motor set, compared to this kit + 2 motors of 80,- a piece).

Is this correct, or am I missing something? Are the hub motors really that much worst? Or are there more budget friendly direct drive motors out there?

The rest of my wishes still apply:

I would be willing to save up a month more, if the increased budget will improve my board significantlyā€¦

Iā€™m sorry in advance if I ask a lot of questions, I will ask more :). I just want to do this right the first time.

Thanks!

We like KEDA motors, right? (KEDA 63-64 190KV Brushless Outrunner 10S 2000W)

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A majority of the hub motors that are available are cheap shitty ones the exceptions are hummie hubs probably the raptor hubs as well. There is also gear drive systems out there from @3DServisas and they are based in EU so more accessible for you.

Keda are great sensorless motors for the money. Iā€™ve used them on 2 single builds and they are still going strong 18 months on.

They are also happy at 12sā€¦

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How wide of a belt is needed for a HDT 3M belt to transfer 700W? Its a brushed DC motor so it wonā€™t have much torque anyway

On the current setup Iā€™ve got 15mm from the wheel to the mount, so the best I can do is probably 1mm for each pulley guard and 1mm for clearance (each for belt to guard and guard to mount), so 11mm belt?

They are low-quality and donā€™t have sensors. But they are functional. I donā€™t like them not having wires coming out for the phase leads. The windings are just extended outside the motor, there is no termination inside.

Whatā€™s a good cheap motor around 700-1400W

why do you want that low of watts

10s2p with 10A max per cell

Is this for your dog? 20A would be balrely enough to move @darenoā€™s right leg.

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