Sketer This is what I made to keep it cool. What are you guys doing?

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Mazin said:
Wonder if putting some holes in the skirt to allow some pass through air would improve those numbers.

Btw if You get up to 25 post you could possibly win a Kronos and be able to tinker with that as well!
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Yeah, this is a very good approach in general - somehow it does not makes sense to put the motor in a place where natural airflow is limited (by all those plastic walls around) and then adding a fan to generate airflow … however, if using a fan I tried to summarize the options for myself:

The placement of a 30mm fan behind the motor (which I did) seems not to be very effective - therefore I will remove it 😢

The Corally motor holder (as mounted by The Stig) looks sweet with the two tone tie raps ;) but it is made of plastic and if I put something on the motor, it should be a material that at least conducts heat. If the fan stops working for any reason, I am afraid that with this holder the temperature could get higher than without it.

DaniC said:
Dual fans like these ones work a treat! These might not be the right diameter for your motor but you get the idea.
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I was looking into this dual fans yesterday. Either from Yeah Racing or other brands, they are pretty much the same anyway and I guess they would work well. Also I like the idea that if one fan fails there is still the second as a sort of backup. But the issue is that the version for 40mm motors is 58mm long … and with this on the Kuron 725 you come very close (for me too close) towards the motor cables:
IMG_1235.JPG


Finally, I decided to try an aluminium snap-on heatsink with a 40mm fan on top (should be more effective than the 30mm ones). While there are many snap-on heatsinks for 36mm and for 42mm motors on the market, it was quite hard to get one for 40mm motors – but luckily I found this one (be aware, there is a similar one with part number 2310037 which is for 41-43mm motors):

Absima.JPG


Ordered it already, once mounted (should arrive beginning of next week) I will take a photo of it.
 
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The snap-on heatsink arrived today and fits perfectly for the stock motor … get’s on very tight and once it is in place you can’t move it anymore!

Currently it looks like that:
DB215422-B31A-494B-95B0-F048D31451C4.jpeg


The fan of this set is ok, but not strong. It’s one of those cheap basic fans (I measured 0.1A current at 6V), so I ordered a 40mm rocket fan and will keep the original one as a spare part. Weather forecast is good … so I am planning to do some motor temperature measurements later this week as soon as the rocket fan arrives ...
 
My Sketer is in the mail...along with some spare parts and a new TC 30mm fan to try out in that vertical position. Still chilly in the northeast right now...will see if it provides enough cooling when summer rolls in (in about 4 months!).
 
winterlong75 said:
My Sketer is in the mail...along with some spare parts and a new TC 30mm fan to try out in that vertical position. Still chilly in the northeast right now...will see if it provides enough cooling when summer rolls in (in about 4 months!).
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As long as it was stock, the motor did not get hot at all with the outside temperatures now. I also believe it would be ok in summer without a fan, but the 30mm in the vertical position should be sufficient to put you on the safe side.
In my case due to the bigger wheels it did get a little hot now already, therefore I try to optimize as much as possible to have enough margin for summertime. I think the most efficient approach is to guide the heat out of this pretty closed area where the motor sits to a place where it gets easier cooled down by the natural airstream when driving ... therefore my try with the snap-on heatsink.
 
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winterlong75 said:
My Sketer is in the mail...along with some spare parts and a new TC 30mm fan to try out in that vertical position. Still chilly in the northeast right now...will see if it provides enough cooling when summer rolls in (in about 4 months!).
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Nice, really interested in how you fit the fan.
 
Today it was sunny and about 20 deg.C / 68 deg.F – perfect weather for motor-temperature testing!

To get the motor stressed I did run on grass, each time for 5 minutes with mostly full throttle ...

IMG_E1256.JPG


... the only downside of this was that my 5400mAh packs did only last for 10 min. each! o_O

However, here are the motor temperatures (measured with a thermocouple, so should be quite accurate):

Run #1/ No cooling (stock): 65 deg.C / 149 deg.F
Run #2/ Heatsink on motor with fan switched off: 57 deg.C / 134 deg.F
Run #3/ Heatsink on motor with fan switched on: 45 deg.C / 113 deg.F

Overall, I am satisfied – the result from run #3 shows that the motor gets cooled down significantly and there should be also enough margin left for hot summer days as well.

With outside temperatures up to what it was today, I will probably only use the passive cooling by the added heatsink (by the way, this is comparable what I measured with the 30mm fan placed behind the motor) … and when it gets warmer, the fan will be switched on.
 
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FunnyCar said:
Today it was sunny and about 20 deg.C / 68 deg.F – perfect weather for motor-temperature testing!

To get the motor stressed I did run on grass, each time for 5 minutes with mostly full throttle ...

View attachment 1902

... the only downside of this was that my 5400mAh packs did only last for 10 min. each! o_O

However, here are the motor temperatures (measured with a thermocouple, so should be quite accurate):

Run #1/ No cooling (stock): 65 deg.C / 149 deg.F
Run #2/ Heatsink on motor with fan switched off: 57 deg.C / 134 deg.F
Run #3/ Heatsink on motor with fan switched on: 45 deg.C / 113 deg.F

Overall, I am satisfied – the result from run #3 shows that the motor gets cooled down significantly and there should be also enough margin left for hot summer days as well.

With outside temperatures up to what it was today, I will probably only use the passive cooling by the added heatsink (by the way, this is comparable what I measured with the 30mm fan placed behind the motor) … and when it gets warmer, the fan will be switched on.
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Good info. Still thinking of putting another fan on my Sketer. Got a motor mounted 1 and want to put 1 on the side also. Locked with 1 screw and loctite 😉
 
Yes, it’s the same - this sort of “high-speed” fan is sold under various brands (and various prices😉) … the one from your amazon screenshot looks exactly like the one I had from amazon (I have returned mine already), which was about 12€:
1892659A-3C10-4F13-9257-E1A7A951475F.png
 
Because finally I went for the Snap-on heatsink with the 40mm fan, which is much more effective … so I didn’t need it anymore. But don’t worry, the fan itself worked fine.
 
FunnyCar said:
Because finally I went for the Snap-on heatsink with the 40mm fan, which is much more effective … so I didn’t need it anymore. But don’t worry, the fan itself worked fine.
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Where did you got it from. Need a heatsink and the fan as well. Sketer is getting to hot 🥴
 
I got my heatsink from a local dealer here in Austria (www.lindinger.at), but the shipping costs would be €9.95 to the Netherlands. However, you could also search by "Absima 2310036" to get this specific one somewhere else. Maybe there are also very similar ones in other shops - just ensure that it is for a motor size of 38-40mm (then it fits very tight on the Kuron 725) and that it is not too long (the length of the Absima is 47mm).

1653996957200.png


The fan which is delivered with the Absima heatsink is not very strong. I replaced it by a 40mm aluminium rocket fan. There are several models on the market for about €20. I have ordered mine on amazon.de ... it is this one:

1653996520132.png


As a protection I also added this on the top:

1653996713816.png
 
FunnyCar said:
I got my heatsink from a local dealer here in Austria (www.lindinger.at), but the shipping costs would be €9.95 to the Netherlands. However, you could also search by "Absima 2310036" to get this specific one somewhere else. Maybe there are also very similar ones in other shops - just ensure that it is for a motor size of 38-40mm (then it fits very tight on the Kuron 725) and that it is not too long (the length of the Absima is 47mm).

View attachment 2439

The fan which is delivered with the Absima heatsink is not very strong. I replaced it by a 40mm aluminium rocket fan. There are several models on the market for about €20. I have ordered mine on amazon.de ... it is this one:

View attachment 2437

As a protection I also added this on the top:

View attachment 2438
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Thanks bro. Will have a look here.

The Stig said:
Thanks bro. Will have a look here.
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Will this one fit? Hobbywing and cheap. There is also a 44mm one but i think that one won't fit
 

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