50mm motors disadvantages?

Hi I see 63mm motor on the majority of the builds I got dual 6354 motors on my daily driver. I don’t see so mutch 5045,5050 etc etc only on prebuild kits/boards.

They got a good power to wright ratio so what’s the negative part of ex dual 5055 motor setup let’s say dual vesc 4.12 and a 10s4p (30Q) battery.

Except for less power what are the other drawbacks on 50mm motors?

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less mass, so they get hot faster. for a mid performance board they are usually ok.

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Daily driver board 85kg rider not to many hills but they are a few. Will that overheat em to?

What’s better 4 cooling the motor rear mount like Evolve or under the board like Boosted?

If you look at the aero of a board, I would imagine that the separation and stagnation zone at the very rear of the board would end up getting more eddy air, possibly cooling the motors more.

However, depending on how the enclosure is designed, the motors under the board may get more straight through streamlines, hard to say. Overall I would imagine the rear would have marginally better cooling.

Maybe in the end it doesn’t matter too much, my motors don’t really get super hot. In addition, if you have metal motor mounts they help to soak up a lot of heat. In my build, the motor mounts and even the entire truck work to keep the motors cool, acting like a giant heat sink, whereas the original Enertion mount doesn’t transfer heat as well.

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That’s some good info. Learning more and more daily here.

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I wonder if adding thermal paste to the surface between my motor mount and motor will help much. I notice in my configuration the mount doesn’t heat up much despite the motor burning my finger tips off.

The anodization of the mount and not perfectly flat machined surface of the motor where it screws to the mount probably contribute to this low heat transfer ability.

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I was just wondering that too but since mine transfers heat pretty well I never bothered.

I think the paint and anodizing definitely reduce the heat transfer coefficient of the surface though (i.e. my old TB motors and TB mounts). What mounts do you have?

Yeah for your application the lack of contact could be doing that, the thermal past might fill those gaps and allow it to transfer well, my surfaces are both perfectly flat so that makes sense.

Overion motor mount and the maytech 6880 which also has a colored surface where the mount and motor join (anodized? paint?)

I might actually try sanding these 2 surfaces with really fine grit to remove the coloring and see if paste helps.

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Could be a fun experiment.

Back to the 50mm motors though I wonder how much of a power difference there actually is, I was thinking about doing them on a build for another client because they have such a tight budget and are quite light in weight.

don’t Evolve use 50XX motors? Their boards have seemingly good range, advertised at 31 miles with their 10s4p pack. Is the smaller motor and slower speed making them have this range?

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Yeah I think so, and somehow they still manage to overpower 6355 motors which I really do not understand, seemingly anyway, according to some tests I have seem by Jun Kami on Youtube

I wonder if their current draw is just that much smaller. I have heard that 10s4p will only get like 12 to 15 miles on one of our boards, I can’t attest since I’ve used lipos this whole time but maybe that is true. Eventually I would switch to liion cells but I don’t have the cash for 60 30T’s or 60 30Q’s

I have used 50mm motor for a long time, wouldn’t recommend for anything more than flat, they get extremely hot, even more if you don’t have a temperature sensor installed and let it cook

Comparing a 6355 to a 5055 190Kv motor, the first has around 18 mOhms internal resistance, the latter 40 mOhms, so for the same current (torque) you will have roughly twice the heat loss, in a motor that has less mass to soak the heat and less surface area to dissipate it

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Would it help if the motors where white as it doesn’t absorb heat like the black colour of most motors does

download

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HAHAhaha Oh mY lOrD

2f7

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No, to run them cooler you would want them painted blue. Red is for higher speed and green for better efficiency of course.

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Just edit your post to: Would it help if the motors where white as it better reflect heat from the sun? :laughing:

And I would tell you I had white Trampa motors and it doesn’t help, they get sizzling hot just like black motors.

This is fake news

This is true for sure

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When you paint them red you get bonus power from Skatan too, at least like 500W extra.

LHB can confirm @longhairedboy

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I’ve actually tried the paste and my motor mounts got a lot more heat transfer to them. Before, the mounts felt warm to the touch and after they felt as hot as the motors did.

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Don’t mind them, it’s much easier to watercool the motors using jamjars.

If you want to wick heat with paint, then nothing beats copper colored paint, but only if you use 3 layers or more.

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