Electric motor got up to 184 degrees
 

I was trying a new battery in my setup (RX8, T8 1900kv, 47t/15t gears) it was a high discharge nano-tech battery and it made the car noticeably faster, people were asking me about my setup and why it was going so fast and I had to give credit where it was due, it was my 5000mah 45c-90c 4s nano-tech lipo I just got, its first time out on the track.

When I pulled the car off the track though I noticed heat eminating from the motor when I had my hand around, and it wasn't particularly hot out. I checked it out and the temp gun said 184!

Im wondering if I wasted my money on this battery, it clearly makes the car fast like a bat out of hell, but I don't think I can use it short of some significant changes to allow the use of this high-discharge battery.

I dont know what the max c on my normal battery is, its 40c minimum so probably around 80, but I never get over 160 fahrenheit on that battery, usually well under it.

Anyways, is there anything I can do to accommodate the new battery without frying my motor, or am I too dangerously close to destroying the engine at those temperature levels?

Perhaps I should retard the timing of the motor in the Hotwire, or put some holes in the buggy body?

184? Call me when that thing is 210+. 160-170 is ideal.

Really though, just drop a tooth or lower your current limiter if your not comfortable with that temp.

Sounds like you have the car geared with some older maybe worn out batteries.

:tire:

Edit: also 4 pole motors (t8) dont work well with a lot of timing. get rid of the timing first imo.

Take all the timing out of it and gear it down 1 tooth on the pinion. It's also possible that with the extra power, it resulted in more wheel spin and therefore more heat.

can you post your setup(esc) track size,what buggy,how much run time was this

i dont know man i think 184/190 degress is fine inless the smaller 1/8 motors are supposed to run hotter than that.

i run a 2200kv castle motor on my 1/8 e truggy and at 184/190 degress it runs fine the motor just runs warm or a little hot.

are you running a 4c with 25c lipo because ive noticed inless i was running a bad lipo but that will heat it up a lot and clog up .

i dont know man i think 184/190 degress is fine inless the smaller 1/8 motors are supposed to run hotter than that.

i run a 2200kv castle motor on my 1/8 e truggy, and at 184/190 degress it runs fine the motor just runs warm or a little hot.

are you running a "4c, with 25c lipo" because ive noticed inless i was running a bad lipo but that will heat it up a lot and clog up .

sorry double post my comp is messed up .

Well come to think of it, I did get a ton of wheel spin, everyone told me under 160 was safe, and I figured 184 was way too much, or Id ruin the magnets inside the motor (this is just word of mouth, asides Nikola Tesla's original design I have no idea how electric motors work other than heat is bad for them) It was like a skating rink out there, I was getting squirrely if I got on it too much.

THere was a straight line where I would smash just about everyone, I think even the nitros couldn't keep up with me for shat down the straight due to the insane torque I was getting, it was almost unfair, but they would smash me in the turns where it really counts.

Ok so 184 is fine? Ill try it again tomorrow, actually I have a 16t pinion in reserve I was hoping to go to that if people on this forum thought it might be ok for me, Ill hook it up to the hotwire before I run it tomorrow and turn the timing down all the way cuz torque is not an issue and these high discharge batteries compared to when I first bought it, when i first bought it, 25-35c was norm for a 4s 5000mah lipo, but Im figuring with the higher discharge of the newer batteries of course things are going to get much hotter.

I just wanted to check here because the motor has been VERY good to me, its the one thing on the car that never breaks and I want to make sure that Im treating it well in return. Like I said, I really dont know all that much about electronics, Im more a 1/1 scale drag racer at heart, had a 330whp MR2 Turbo that ran 11's, so I don't really understand this new hobby I have gotten into and appreciate the n00b friendliness of this forum.

edit: need to respond to previous post.

Dirtburners track ( dont know how that compares in size but lets just say large) 15-20 minutes straight run time, Losi 8ight 2.0 converted to E.

in my opinion i think 184-190 is fine temp wise, if you touch the motor and its so hot that you cant hold your finger on it for a sec or fry a egg on it than its way to hot !

yes you dont want the magnets in a electric motor to get hot for sure !
i think 30c or higher 4c lipo is ideal to run for efficently and power.

I do agree with you about the motor running, 150-160 degress it will give you to much wheelspin i expreience it on a dry dusty track it might work better on a moist track though.

i run 30c 4c lipos on my truggy.

So yay or nay on experimenting with the 16 tooth pinion for the motor?

I would ask in the tekin thread, they may have a more definitive answer for you. I fear that if you drop to a 14t you will actually have more wheel spin, but I could be wrong. I would lower your current limiter to around 75, and put on the 16t. take the motor temp after 5min of running and again after 10min. generally if the motor is really hot and the esc is cool you need to gear up a tooth. this however does not always hold true. Randy Pike at Tekin runs or at least used to run a losi 8 2.0 so he should be able to give you an exact answer. Hope this helps.

Also make move the motor away from the spur gear and make sure that everything in the buggy is moving freely. I have had my motor temps go up as much as 40* because of bad rear hub bearings.

I would keep it geared the same and add some torque control. Start out at 50 and go up from there if you have any trouble getting over any jumps with short run ups. Not only will it help with heat but also help accelerating out of corners more acurately. Another thing that could help is taking away some brakes. I run mine at around 65%. Enough to stop the car reasonably but not to touchy.

Also for better help, Car, track info would help too.

This car flies like a bat out of hell on the current setup with the high discharge battery. No trouble clearing jumps AT ALL. Id like to keep my temperatures cooler, so Im thinking, with your guys approval, retard any timing that was added on the hotwire, possible dremel some holes in my cars body, and do they make a cooler for the Tekin T8 1900kv?

Could use some opinions from more experienced RCer's as Im beginning to think I bought too much car for my first RC with the power this one has and my weak driving skills.

What is torque control?

bring your current limit down to 80, and you should see a noticeable drop in temp. you can't even feel the drop in torque. :nod: