Kraton Hobbywing 4985 1650kv cooling

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DKPatriots said:
I've heard that this fan and heatsink work on that motor, but I don't have one myself so I can't gaurantee it.

https://www.amazon.com/dp/B07ZPMTZX...abc_4TZR4DXNS6RZ0ZR6G0TQ?_encoding=UTF8&psc=1

The heatsink is designed for 40mm motors butncomes with four spacers that allow it to fit around larger cans.

Too hot is over 170-180F, which is about 75-82C. Past that and you risk the heat weakening the magnets. Guys like to keep them at or below 160F (about 70C) so that you have a bit of a buffer between the running temp and the max safe temp. As with many things in electronics, cooler is better.
Click to expand...
I have the exact same motor (4985 1650kv) on my Kraton and I also had this heat sink on my old 2050BLX motor...and I cooked the BLX.
That heat sink (above mentioned) won’t fit on the 4985 plus it burn my BLX so I wouldn’t risk it again. The under plate keeps too much heat in the underside of the motor so in not a fan of this heat sink.
My motor gets that hot and I’ve not had an issue but it’s only 4mths old.
 
The heatsink above fits just fine on the 4985, have it myself. You just have to stretch it a little and this one bends easily. Just get longer screws. The 4985 runs significantly cooler and can't be compared to the stock BLX. Heatsink and one fan is all it needs while stock needs 2 more powerful fans.
Post #34 even has pictures showing it installed.
 
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R35 said:
I have the exact same motor (4985 1650kv) on my Kraton and I also had this heat sink on my old 2050BLX motor...and I cooked the BLX.
That heat sink (above mentioned) won’t fit on the 4985 plus it burn my BLX so I wouldn’t risk it again. The under plate keeps too much heat in the underside of the motor so in not a fan of this heat sink.
My motor gets that hot and I’ve not had an issue but it’s only 4mths old.
Click to expand...
The heatsink definitely fits the 4985. It's super soft aluminum and very easily fits right on. myself along with a bunch of others have it. Before I had this heatsink I couldn't touch the motor after one pack. Now the motor is cool to the touch.. works for me 👍
 
I've ordered a whole bunch of stuff from Alza for a dual fan set up for the motor so will post some updates/pics once it all arrives
 
M240i_bandit said:
Hi Guys,

I couldn't find anything concrete on a search but need a little help - I've got an EXB with the Max6 combo/1650kv on 18T which seems to be running a bit warmer than I'd like (can't keep my finger on the can for more than half a second)

I bought a K8s heatsink and fan but I'm not sure it it'll fit - has anyone managed to successfully fit it? It fits around the can, and would need stretching over the fins which seems achievable - but I'm more concerned about the lack of clearance underneath the motor. Once it's on the motor it doesn't look like it'll be easy to pull off so a bit hesitant to just give it a go

On a side note how hot is too hot for these things? I'm estimating the can somewhere around 70C give or take

Cheers
Daven
Click to expand...
Please get a cheap Temp gun. And post your temp reads here.
Because it is anyone's guess how hot it is. Including yours. 🤷‍♂️
Internal temps of 212F is max. External temps of 160F max and lower is ok. Never exceeding this.
Can your finger "guestimate" Temps. at 70C, ????
I doubt it. I know mine can't.:LOL:
Get a temp gun.👍
 
SrC said:
Please get a cheap Temp gun. And post your temp reads here.
Because it is anyone's guess how hot it is. Including yours. 🤷‍♂️
Internal temps of 212F is max. External temps of 160F max and lower is ok. Never exceeding this.
Can your finger "guestimate" Temps. at 70C, ????
I doubt it. I know mine can't.:LOL:
Get a temp gun.👍
Click to expand...

:ROFLMAO: well it was more of a deduction - like I know I can put my finger in 50C water for a min or 2 before it becomes uncomfortable and I know how instant the pain is of spattering 90C water from a kettle on my hand + I regularly use a meat thermometer to cook my chicken to 75C ish so I know what that felt like when I touched it so I knew it was somewhere between 60 and 80 - > guesstimate 70C give or take :geek:

I think either way I'd like to get to a situation where I can comfortably keep my finger on the motor so I know it's not anywhere near being thermally strained I.e 50C odd

Having said that a temp gun is on my shopping list (y)
 
Just drawn up these brackets , need to get them laser cut. they will just fit between the motor mount bracket and the motor with 2mm longer screws, the extra holes are just so i can find the best position angle when fitting it.
The double one was designed around HW1650kv the single will work on a HW1650 or a 40mm motor
fan brackets.jpg
aiming to fit 1 or 2 of the following, depending what i can make work. I can supply the flat pattern dxf file if anyone is interested.. PM me
fan and switch.jpg
fan mock up.jpg
 
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Looks cool but I would eliminate the fancy grill under the fan, it will limit air flow. 3 bars (120deg) should do a better job but honest;y you probably do not need anything for structural support.
 
Looks cool. I thought about getting a 3d printer and make small misc parts to sell on ebay.
 
Fair enough, honestly I'd just cut a big hole. If you are bashing/jumping make sure you pick a fan with strong structural support. Those fins come in 1-2mm sizes on some fans. The 1mm will crack in no time. Even though this will be stainless, make sure you can somehow support the other side as well or these will bounce like a spring on impact. A simple standoff that supports against the motor might do it. If this is for speedruns that wouldn't be needed.
 
Yeah im expecting some bounce off it on landing and had thought of a small packer or something at the back end for support, there is a 15mm gap under it to the motor to allow for some spring and also not to get affected by magnetism from the motor. ill get them cut and bent this week if i can and post pics here when its done.
jkflow said:
Fair enough, honestly I'd just cut a big hole. If you are bashing/jumping make sure you pick a fan with strong structural support. Those fins come in 1-2mm sizes on some fans. The 1mm will crack in no time. Even though this will be stainless, make sure you can somehow support the other side as well or these will bounce like a spring on impact. A simple standoff that supports against the motor might do it. If this is for speedruns that wouldn't be needed.
Click to expand...
That's the reason i didn't go for the big hole tbh, seen a couple of vids with these kind of fans and centre's are dropping out after a big hit, so i added that in just to help it. seen it happen with the alza racing esc fan mount that doesn't have a center support, so decided to be safe. I can always cut them out if I don't like them , but cant add them in if I don't, if you get my drift?
 
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M240i_bandit said:
Hi Guys,

I couldn't find anything concrete on a search but need a little help - I've got an EXB with the Max6 combo/1650kv on 18T which seems to be running a bit warmer than I'd like (can't keep my finger on the can for more than half a second)

I bought a K8s heatsink and fan but I'm not sure it it'll fit - has anyone managed to successfully fit it? It fits around the can, and would need stretching over the fins which seems achievable - but I'm more concerned about the lack of clearance underneath the motor. Once it's on the motor it doesn't look like it'll be easy to pull off so a bit hesitant to just give it a go

On a side note how hot is too hot for these things? I'm estimating the can somewhere around 70C give or take

Cheers
Daven
Click to expand...
I used the XMaxx heat sync to mount my fans on the same setup as yours.
 
SrC said:
Alu will bend from impacts. SS may be stiffer. IDK. I would rather strap/clamp the Fan mount to the motor. Not sandwich the the mount where the motor mount attaches.
Click to expand...
I think he meant alu fans rather than bracket. Strapping or clamping to motor just adds more weight to the motor giving more chance of stress, going direct to motor mount removes a lot of excess stress on the motor bolts. Plus with the extra holes around the bracket allows for 2 c/s short bolts at 90deg to main fixings directly into the motor. Heat sinks on hw motors are not as effective as some other motors due to its fins. Each to there own though, just put it here to show an idea to others for inspiration.
 
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