micah11

I've decided it's time to replace the fried motor for my 2wd buggy. It's a Leopard Hobbies 3900~ish Kv, and it wasblazingly fast on 3S..for the 1st run, then the next time I ran it, it had about 1/2 the power, and every run after that i got higher temps, and lower power, until it just crapped out. I'm fairly certain it's just the motor, even though the ESC was pretty hot some of the time.
So, I'm looking for a cheap motor to replace it with, like this one. I've just got one problem. I can't seem to figure out what allen wrench fits on the pinion gear. I also have no idea what pinion to get, concerning pitch and tooth count. And, last question. Pretty sure I'll have to put on new connectors for the motor, will this soldering iron work? Or is that too cheap?

john01374

Micah11- You need to be careful when buying HobbyWing motors. A large number of them like the one you linked to are actually 380 sided motors in a 540 sized can. The dead give away is the fins on the motor can. For a 1/10 scale buggy you need a real 540 sized motor.

I bought one of these 3800KV QuicRun motors a couple of months back to run in an old RC10 and it works great. I've got about 15 pack through it without any issues. http://www.ebay.com/itm/HobbyWing-Qu...item20fb2fd204

As for gearing. We need to know more about the car you're running. Odds are the reason the motor burned up was the gearing. The gearing was most likely too high for running on a 3S pack.

What kind of car are you running and what is the current gearing? Are you running the stock sized tires on the buggy? Pics are alway helpful.

micah11

The car's a Redcat Twister xb, the pinion gear has 23 teeth, the spur has 77. I'm running Proline Dirt Hawg's, I believe they're 2.2". They're a bit larger than stock. As you can tell by the pictures, I really stuffed that 3S in there. It really did fly when it was working, lol. Thanks

SyCo_VeNoM

soldering iron... I've tried 35watt irons, and honestly I find they take too long to heat up the wires a 40watt won't be much different.
For RC motor, and battery wires I use a 240watt solder gun that heats up in like 10 seconds flat. Only thing is you have to be careful with them as they can burn out, or melt the wires if you have it on the wire too long

as for the motor kv if you want 3S 3900 kv is kinda high I'd go 3500to maybe 3200kv personally.

EXT2Rob

My Feedback: (1)

Oh yeah Micha, you need to get yourself an infra-red thermometer. Duratrax sells one for $24. Your car is very much like an Evader, I've had two, and I'd say your pinion gear needs to go down a couple-three teeth. Your motor shouldn't be allowed to get over 160F, or the magnets will start to loose strength, and the motor, power. Probably what happened to your Leopard. The ESC should run around 125-135F or less. Check all your bearings, you may have one or more that are getting gritty or even locked up. Drag will cause your motor to overheat. So service/replace any bad bearings.

I have run the 4300kv version of that HobbyWIng motor in my Evaders. Personally, I think it's a perfect match for the Evader. Thing only weighs 3.5lbs, so that little 340-size motor had plenty of torque and top speed. Wheelies were no problem on asphalt, and it would top out at 40mph on stock gearing and 2S. 3S would be insane without gearing down a few teeth, which is what you usually do when going from a 2S to a 3S setup. Helps keep motor temps down.

micah11

I had a Redcat Caldera with one of those 380's with fins on it, and it pulled it along pretty good, so I figure it should be good enough for a 2wd buggy, right? I'll have to take a look at those IR thermometers. What do you guys think about this Neewer Motor? It's definitely cheap, but it says Max amps:41, and ESC: 60a. I've got a Lansu 90a esc on the buggy, so.. that wouldn't work, right?

SyCo_VeNoM

it wouldn't matter the motor will only pull as much as it can pull a 41A motor can only pull 41A's no matter what even if you had a 320A ESC it would still pull 41A's

as for 380 sized motors just cause one RC can run it doesn't mean the next can
example I have a 1/10th scale tamiya buggy it runs the 380s happily. No matter how big of tires I slapped on that RC it happily chugged along with that motor.
I put one in a 1/16th scale truggy the motor got hot as hell in seconds even though the RC is physically smaller I had to go to a 540 motor. A lot has to do with the gearing, drive chain setup, and weight.

EXT2Rob

My Feedback: (1)

Oh yeah, Syco, it does depend on the car. That's why the OP needs an IR temp gun. I've seen you around the forum, Micha, you've been here for a while, you should have one by now. It's really one of the best diagnostic tools in your kit. How else you gonna know when you have a bearing going bad? Monitoring your motor temp, especially at first to get an average baseline, is the best way to make sure your car is running as it should. If you notice that the motor temp has gone up significantly, 10-15 degrees, and it's the same temperature and conditions as the day before, you know there's something needs looking into.

Weight of the vehicle makes a huge difference, probably the most difference, as far as motor choice is concerned. Cripes, Syco, I cannot believe HoBao specs the same dang motor in the Hyper 10SC short course truck as it does in the Hyper 10TT truggy (about a pound lighter at 4.5lb) and I use that motor in a 2wd Evader! How could they even think that little motor (as respectable a little mill as there is) could push a 5.5lb SCT with any kind of gusto with out over heating in 2min? Well, gearing, I suppose. But it sure wouldn't be fast.

DieHarder

I totally know what you mean. I have a 60W and it sucks on anything bigger than 16AWG. I use a 100W for that stuff, but even at 100W it just barely makes it through 10AWG.

micah11

I'm thinking about getting this Quicrun 3800kv. Will those connectors fit what's on the ESC? Right now it's got these bullet connectors, and it looks like it'll fit, but I'm not sure. And last question, what do you use to get the pinion gear off of the old motor? This will work, right? And this pinion should be good, too. Just want to make sure all my ducks are in a row before I start spending money,

SyCo_VeNoM

Beats me I tried a 380 in my jammin .5 crt, and it got hot as hell which is what I think they recommend for the SCRT10 (which has the exact drive train).
Hell I even had to get a servo meant for a 1/8th scale as that sucker was eating servos as light snacks.
I remember the first time I tried converting a nitro into a electric, and using a brushed motor as a test. After a 20 feet you would have sworn by its looks that it was still nitro it was shooting out so much smoke lol
Speaking of SCT's I really should get a motor for my one as its been sitting here around a year with no motor lol


hmm if its a 1/10th scale HW esc it should fit. If not you will have to order 3 pairs of bullet connectors(they don't cost that much) and solder them on.

The driver to take off the pinion... you should just get a set something like http://www.ebay.com/itm/4-in-1-RC-Mo...item27f48a095d
For the record I have one of the ones I linked works pretty damn well. I only say a set cause sometimes you need other sizes, and it would kinda suck if you only had the one, and paid that much for it.

micah11

Oh boy.. I just took a chance on this.. I couldn't for the life of me find a 3.175/3.2mm pinion that wasn't in china, so I picked up this slick guy: A 1/8" to 5mm pinion adapter. Anyone have any experience with those? I also dropped the pinion tooth count down 5 teeth, from 23 to 18, that should be in the right range now. This RC thing really likes spending my money.

cumquat

for pinions, your best bet is robinson racing. you can find those at towerhobbies.com . they make dang near every type of pinion. only 2 i cant recall seeing are .6 mod and 64p gears with 5mm holes. they even make a 47t 48p pinion and a 49t 48p spur! they're bount to have what you need. now, i dont recall if redcat uses true 48p gears or .6 mod gears. someone who has experience with them ought to be able to shed light on the matter. i remember one of the chinese brands uses .6 but cant remember if it was them, himoto or one of the million others that i have forgotten.

phmaximus

sorry I have to disagree with that... And I'm going to have to call it...

why do you say that?? Is this just a once off isolated problem??

Im interested to know more because I've owned at least 5 of the combos and 16 odd RC cars, and I've helped a bunch of people on this very forum with these 380 core motors.... Everything from my experance contradicts what you are saying and it makes me think u might oh had a issue with a 380 core motor?? I just hope that it was not a once off isolated issue and you are not reposting other people's opinions.... Cuz that would suck.... Imagine following someone's advice only to find out they have never used the product of only have used it once.

DieHarder

Redcats use Mod 0.6

cumquat

thanks.

for some reason robinson calls their 0.6 gears "metric".

micah11

Alright, got everything in today, installed the motor, and it only runs in reverse and has low torque at that. Why?!?!? I'm this close to throwing this car out the window right now.. Is it the speed control? It's the stock Lansu 90a esc. It got hot a few times with the old motor, but always went into overheat protection. The old motor when it crapped out, had no reverse. I've tried changing the Tx settings, the motor timing on esc.. nothing. If you guys fairly certain it's the esc, anyone have a cheap one you can recommend?

RustyUs

http://www.ebay.com/itm/HobbyFans-Br...item43cc63ee7f

These were the cheapest 60A ESC I could find at the beginning of the year. If you are in the bidding mood, there is a few of them over on eBay just waiting for somebody to jack up the price . I personally wouldn't pay anymore than $24 shipped, but supply and demand equates to price increases. Back a few months ago you could "Buy It Now" for $22.

I have two of these ESCs. One has been put into a B4 buggy. I run the ESC without the fan on and temps are always fine when running a 3650/540 sized 3930kv motor on 2S power. The ESC has been beaten, tossed around, ran in 98°F weather, and I couldn't be happier. A HobbyWing program card will also work adjusting the settings. The second HobbyFans 60A ESC I bought just sits here as a backup or possibly be use in a new buggy build.

Only down side, you have to put on your favorite connectors and it uses 14 gauge wire. I have never had an issue using 14 gauge wire on any lite 1/10 2wd RC.

Update: Haha. Minutes after I typed this post, I took my buggy out for a run on the track at sundown. 10 minutes later, the buggy is acting up. It would go all out for about 5 seconds and then shut down for 5 seconds. Over and over again this happened,....overheat protection (green flashes on LED). Time to put the fan on. Go figure .

Note: I must point out though that I'm hard on my ESCs. Most of the time I run my RCs at 50% ~ 60% throttle. By doing this for any length of time, the unused power from the battery has to go somewhere. Right? The ESC takes the brunt of it in the form of heat. And is why, I guess, I should be looking for lower Kv motors.

SyCo_VeNoM

generally when you lose a direction(and have tried re-centering the trims, and recalibrating the ESC) the ESC is shot

rufus2000

For what it's worth the 380 hobbywing motors on 2s work really good on 1/10, if you pick the right one. Plus, they're lighter. We've ran them on touring, buggys, stadiums, shortcourse you name it.
Our spec motor system for some of the classes here is the hobbywing 13T with the ez-run 35/45amp ESC. Very high quality and super reliable, we've had those for at least a couple of years. Zero issues.

Just make sure to get an original hobbywing (there's some knock offs of both the motor and esc, they look pretty similar).

Also, I notice you're picking a 10T 380 motor. Personally I would not go for that one (I have a feeling heat may be an issue in offroad, plus you do need a bigger ESC- The 35/45 Amp won't cut it as per hobbywing). If you want to run mod or want the ultimate in speed (or run 3s) then i would definitely suggest a true 540 motor as some have commented.

EXT2Rob

My Feedback: (1)

Anecdotal evidence to the contrary: The 35Amp ESC 9T/4300kv 380 motor combo. I've run that system in 2wd STs and in a 4wd Hyper 10TT. Geared properly, never had a temperature issue.

micah11

Oh boy... All the parts came in today, I got that Hobbyfans 60A ESC, and the Turnigy Trackstar 3900kv 380-with-fins motors. Installed it, and apparently it doesn't like 3S power. Ran it for maybe 5 minutes, and then... nothing. Just a little humming from the motor, but it's like it's seized up. In the process of returning it, because it said it was able to take 3S voltage, but it failed. Definitely wasn't abused, I was just putting around with it some. I assume HK is going to give me the money back in store credit. What motor would you guys recommend for it? I'd assume something around 3000-ish kv, cause of the 3S, but idk what's good on HK and what's not.

RustyUs

That bites. Probably the highest Kv rating you want to go on a motor with 3S ...13.5T 3300 Kv. That's the recommended specs from a HobbyWing EZRun 60A ESCs and the HobbyFans ESC.

I think a 3000kv motor would be a great place to start. I would opt for a "full sized" 540/3650 this time.

Also, a little update on my HobbyFans ESC overheating issue, as stated in an earlier post: I'm guessing the reason I even had an issue with the OHP (over-heating protection) kicking in was 'cause of a binding in my B4's tranny. As usual, I should've stopped as soon as the 'clicking' noise was heard. I'm my own worst enemy. I don't even take my own advice when it comes to my old B4. I just beat the snot out of it.

After turning the tranny by hand...it was somewhat of a challenge to do. One of the diff outdrive hubs bearing failed, and threw at least one of the balls into the tranny's gears along with the rubber seal in the mix. I'm almost sure that was causing the motor to strain and also putting a strain on the ESC.

Getting the chewed up gears clean was a chore. Long story short...I put the tranny back together (with less than perfect diff/idler gears); got the buggy back on the track; no more heat issues from the 'el cheapo' HobbyFans ESC.

RustyUs

Oh, just so you know, the HobbyFans ESC does work with my HobbyWing programming card to adjust the normal items like: running mode; drag brake; LVC; punch; maximum brake force; max reverse; timing, etc.
And my new cheap (ebay) TSKY Tyrannosaurus Rex 120A Sensored ESCs that I'm testing,

they also work with the HobbyWing programming card to change the values. I currently have two of these blue re-branded/copied ESCs and another one is on the way. Running one since June in an overweight Yeti with a 550 motor on 3S LiPo packs. Holding up so far.

Next cheap piece to test is a 3660 sized sensored motor. I haven't quite narrowed this one down yet.