Problem with ez 2350kv motor/gearing

Hi I'm having problem with 150 esc and 2350kv motor on 4s on mugen buggy and kyosho 777.
I'm using this kit with 13T pinion, esc is cold but motor get so hot that loose magnetic energy.
I'm lucky I can repair the rotor making it get its magnetic force as new.
My problem is why is this happening?
Is gearing too high or too low? do you suggest triyng a 11t or 16t pinion?
On 3s everything is fine, on 4s I hoverheat the motor in 5 minutes.
Anybody else is using this kit on buggy on 4s? what gearing u use?
thanks
cheers
gab

[suicideneil]

I'd love to know how you fix a demagetized rotor? Sounds like it is still partially toasted and so heats up everytimne you try to run it...

I would gear for ~40mph with 4s lipo, 3s isnt ideal and abit low for a 1/8 scale vehicle.

Chances are you're geared too low- if the esc is still cold (and the lipos too?), but without knowing the diff ratios and the spur size, I wouldnt like to recommend better gearing.

[jsr]

Cool ESC and hot motor means you're overgeared (too short a gearing). As suicideneil stated, not knowing your other gear ratios makes it hard to make a definite judgement, but most buggy/truggy diffs are about 4.3 (approx.) and spurs are usually in the 46-50T range (unless you're talking about CEN or other with 60+T spurs). But going just by the "cool ESC and hot motor", that usually means too short a gearing. Try the 16T to see if runs cooler.
Regarding 3s, I run 3s in my truggy and it runs fine. Many people will say it's not enough without having ever tried it. My truggy runs over 40mph on 3s and the ESC barely gets to the 90Fs and the motor doesn't go over 120F on a hot day. Of course, 4s would be better as you'll pull less current when geared for the same speed, but 3s is plenty to run a 1/8 truck (just make sure your batteries can sustain the current draw). I'm able to keep up with the nitros on the track on 3s, and pass them on 4s.

Hi I have 13 43 at differential and 46 or 48 at spur.
To fix the rotor I simply send it to a company near home which makes rotor and they remagnetize it...already tried, it work pretty well.
If you want try make me know...
Ok so look like I have to use bigger pinion...this is very strange to me I never tought a small gearing could damage anything...
Thanks

[himalaya]

Hobbywing has some great ESCs but for their 1/8 motors I have seen 6 of them de-mag around me and my buddies, even with the huge heatsink/cooling fan attached. It's very hard to gear correctly for a decent efficiency. keep the ESC, go find another efficient motor.

[suicideneil]

Well thats rather awesome, didnt know it was possible to remagnetize them quite like that...

On the motor front, I suggest a medusa 70mm 2000kv item for 4-5s lipo, that would run great.

[jsr]

Motors can be picky. Overgearing (too short) and undergearing (too tall) will both overheat a motor, dropping efficiency, which causes more current draw, which further drops efficiency...it's a viscious circle once it gets started. The HW motors are low-cost entry-level motors. For their price, they perform well. Obviously not as good as the higher-end motors, but those cost a LOT more. At least the HW motors have captured screwed-in endbells instead of press-fit (which even higher end motors use).

[jzemaxx]

HW's ESC's are great, but their motors stink.