Mayhem Mayhem.

[GordonFreeman]

16.8V, 8800 mAh, Fiegao 540 9L, Mtroniks Truck ESC, $100 Mayhem Chassis. Any questions?

[Ventman]

Just one, how good does it run? :D

[TimisTim]

Ummmmm, isn't the Mtroniks truck rated for only 4S and 12 NIMH cells?!? Heck mine heats up quite a bit in my MT2 on 3S/7L combo.

[GordonFreeman]

We'll find out next Sunday.

[Rocksalt]

What are the 3 diodes for? Correct me if I am wrong... but aren't the brushless motors 3 phase AC motors? If so, won't those diodes block the negative AC wave?

[Rtsbasic]

The diodes are provided by Mtroniks and make the controller run cooler, maybe they have a similar affect to a diode accross a brushed ESC's cables.

I have just two questions, a) what batteries are they? And b) are you crazy? :) Be sure to let us know how long it takes for the smoke to come out on that voltage :D You may want to swap to a 25v power cap instead of the factory supplied one or it may leak.

[GordonFreeman]

a) Himodel.com

b) Probably

[campbellspurloc]

I want in on the money pool for how long it lasts before it smokes...I'll take 3 minutes...LOL..JK Hope it works well. Let us know. Also would like to see some more pictures.

[ElectricThunder]

Nice (and 16.8 volts is insane; don't let Mtroniks know...:p)... I have one question however.... Can I have it?:D:D:D

Isn't 16.8 volts also a freshly charged 4s pack (4.2 volts per cell)? :confused: So no real biggie (in terms of frying stuff).

Nice stuff once again though.

[GordonFreeman]

Magic smoke came out at around 20 minutes. This was burning around in a parking lot. Took the tires down to nothin'.

Maybe I did a boo boo by pulling the plate off the bottom of the ESC. But I used thermal epoxy to attach it to the aluminum chassis for a heat sink. I was checking the ESC and Motor temps through the run. It didn't seem like the ESC ever got very hot; so was it the voltage that killed it? I though it was rated to 4 cells.

After I got to it and pulled the battery plugs I noticed the ESC was detached from the chassis. I don't know if that caused the failure or the other way around. Since there was not magic smoke residue on the remaining epoxy on the chassis, I think the ESC came off after it failed.

So the Mtroniks Truck ESC is probably not enough. What's the next best ESC?

[GordonFreeman]

Esc.

[chilledoutuk]

well for a setup like that the new quark 120amp controllers look really nice.

The tried and tested alternative would be some sort of bk warrior but i really dont like the construction of the warrior controllers to be honest.

[Rtsbasic]

Impressive, when I've burnt them up, I've only had goo come out of one side, never both! I think removing the heatsink block was a big mistake, not just because its thermal dissipation but because now its not realistic to expect them to replace it under warranty.

Personally I went for a Warrior 9920 after finding the Mtroniks Truck not enough voltage wise, I have yet to actually run it though, not had the time to fit it to my Emaxx.

[campbellspurloc]

can you clear up something? How many cells were you running 4or5?

[GordonFreeman]

4S (4.2v max X 4 = 16.8v)

I had also noticed the controller would stop the motor on occasion (like it when to full brakes). But it was actually making the motor tic back a forth. I would have to uplug the battery and plug it back in to get it to work again. Maybe a symtom?

[campbellspurloc]

4s setup should be ok with that controller. I thought you were running 5s. Usually most people call a 2s 7.4, 3s 11.1, 4s 14.8. The ticking back and forth is commonly called "cogging". This is when the controller has problems getting started in a forward direction. This is extremely hard on the motor and controller and could have been part of the problem of why it blew up. Someone else reccommended the Quark controller in one of the above posts. I would reccommend their controller too, it would be a good 4s setup. Just make sure to run a separate bec with it.

[cart213]

Could you please post a link to the lipos that you are using? I like the shape of them.

[GordonFreeman]

http://www.himodel.com/en/rc_hobby/electric_969.php but I took the packs apart to wire them into a 4S and to get them into the phyisical config they are.

I know what studdering is (from a stop). But this happened while the buggy was moving. It was like it slammed on the brakes. Then I had no throttle control of it. The motor would be ticking back and forth slowly (2-3 per second). Then I would have to unplug the battery to "reset" the system and plug it back in and then it would work again.

This happend a few times, and apparently it did not like it the last time it did it. But, yea, maybe it was doing some sort of studdering all by itself and that overloaded it. Now that I think about it, I'm sure this is why it failed.

It was marked v1.05. I have a Pro unit marked 1.07 I'm thinking about trying since I've never had that "stopping" problem with that one.

[ElectricThunder]

http://www.himodel.com/en/rc_hobby/electric_969.php but I took the packs apart to wire them into a 4S and to get them into the phyisical config they are.

I know what studdering is (from a stop). But this happened while the buggy was moving. It was like it slammed on the brakes. Then I had no throttle control of it. The motor would be ticking back and forth slowly (2-3 per second). Then I would have to unplug the battery to "reset" the system and plug it back in and then it would work again.

This happend a few times, and apparently it did not like it the last time it did it. But, yea, maybe it was doing some sort of studdering all by itself and that overloaded it. Now that I think about it, I'm sure this is why it failed.

It was marked v1.05. I have a Pro unit marked 1.07 I'm thinking about trying since I've never had that "stopping" problem with that one.

Maybe it was the software's fault that the magic smoke was let out then? If that's the case, maybe Mtroniks will replace it even though you took off the heatsink...lol!

[tcolesen]

My controller that went up in smoke had similar symptoms as yours, and it was v1.05. Mtroniks is up to v1.07 right now, and that's the software they sent with the replacement for my smoked one.

[GordonFreeman]

tcolesen,

Are you using your Mtroniks Truck ESC? With what motor/volt/car? So do you think the Truck controller should work with my set-up? 4S, Feigao 540 9C (black fins) in an 1/8 scale buggy for race conditions?

What other controller should I be considering? Quark? MGM? BK?

[Muck]

That magic smoke smell is hard to get rid of! Stinky stuff. When you put a new ESC in there, it's going to be scared!

[tcolesen]

tcolesen,

Are you using your Mtroniks Truck ESC? With what motor/volt/car? So do you think the Truck controller should work with my set-up? 4S, Feigao 540 9C (black fins) in an 1/8 scale buggy for race conditions?

What other controller should I be considering? Quark? MGM? BK?

I use the Mtroniks Truck in a custom-converted XTM X-terminator 1/8 buggy, on 4s Lipo (14.8v) and 4s LiFePO4 (13.2v) with a Feigao 540C 9L (same as you). I think the Mtroniks Truck should be fine for race conditions, but mine has yet to see that. About a week ago and before that, I was using my own cut chassis with the battery on one side (4s 5400mah 8C Lipo and 4s 3600mah 16C LiFePO4) and the motor on the other. Now, I'm going back to the stock chassis, and have cut a new motor/diff mount (1/4" aluminum), the motor is above the diff (not enough room), and the batteries will be specially/securely mounted to the mud guards. Once I finish this stuff and get some more funds I'll be able to say how well the Truck will do with this motor on the track.

[TimisTim]

Maybe the over amp warning was going off when it was studdering. My first controller went up in a puff in about 5 minutes the first time I ran it. It was doing fine then slammed on the brakes and shut down. The guy at Mtroniks said it was a motor phase that burned up and replaced it for free.

[GordonFreeman]

Hmm...just psuedo testing the buggy now. Using the Mtroniks Pro (rated less than the Truck), holding the buggy down on carpet at full throttle (spinning the tires making black marks on the carpet), my Watt meter only reads 55 Amps.

I think the motor is OK, I think I'll try the Pro ESC on the track tommorow, instead of doing burnouts in the parking lot.

Wish me luck.

[Rtsbasic]

Actually, they're up to 1.07B :p

By the numbers, your setup should have been fine. I thought you was running 5s lipo not 4s lipo which is why I suspected the smoke would come out. You should phone Mtroniks, speak to "Paul Kenningly", and explain the stuttering that was happening then the smoke come out, maybe he'll sort it out for you.

[campbellspurloc]

tcolesen,

Are you using your Mtroniks Truck ESC? With what motor/volt/car? So do you think the Truck controller should work with my set-up? 4S, Feigao 540 9C (black fins) in an 1/8 scale buggy for race conditions?

What other controller should I be considering? Quark? MGM? BK?

Gordon,
If you are truely going to try to race this, how long are the heats going to be?

If you are going to run 5min heats, your motor will be fine. If you are going to try to run 10min heats or longer, NO WAY will that motor make it. I have tested alot of controllers and motors(including the Feigao you listed) in my buggies and the only two motors that can make a long race that I have tried are a Lehner and a NEU. Alot of people will probably come on here and say I am wrong and that they have this motor, but I think 1) they don't race it 2) If they do, it is not in a 1/8 buggy. If anyone wants to dispute me, let's hear how long the race was and how many cells you were putting to it, and how good of a driver you are? Remember, there is a BIG difference between Bashing and Racing. This motor is fine to Bash, but it won't cut it racing a long heat(unless you can't drive and you spend most of your time on your lid) LOL...

As for the ESC, I won't comment because I have not tried the Mtronicks. This is about the only controller I havn't tried. Tcoleson threatened to come out to the track and let me try his, but he has been absent at the track lately???? What up Tcoleson???

Anyway, let me know what your intensions are with the racing and I will give you a reccommendation on a motor.

Campbell :)

[tcolesen]

I'm redoing the chassis on my buggy. Going back to the stock one, with a custom motor/diff mount (as usual). This time I'm able to use a diff because I finally broke down and paid $22 for a single 16mm drill bit. The motor/diff mount is finished, but I still need to cut out a top plate, and then I need that plastic Kyosho plastic spur gear (suppose I should order it soon). I also need to cut out some battery trays from the plate of G10 garolite that I got.

So, I should be able to make it out there the weekend after this coming weekend (damn AP tests!) and be able to run my buggy again. Then, our infamous 1/8 buggy motor/controller tester can have at it!

BTW, anyone want to buy a brand new (from BK directly) Warrior 9920 for $180 shipped?

[chilledoutuk]

campbellspurloc could you elaborate on "NO WAY will that motor make it."

are you infuring that fegao motors break after running more than 10 mins in a race?

or are you saying that they overheat when being raced for that long?

with the amount of happy users of fegao motors on here i think you need to be a little more descriptive about what happened to these motors that didnt "make it".

[GordonFreeman]

Yea, when I say racing, I mean racing. At the Rock Pile (Wisconsin).

I ran/raced it today at the track with the "smaller" Pro ESC (again sinked to the chassis) and it worked just fine. The ESC got up to about 140F, the motor got up to about 175F and batteries about 90F (70 ambient). I ran for 10 minutes, but my intention is to be able to make a 15 minute main. The buggy seems just as fast if not faster than the other guys (Nitro) on the main straight.

One guy I let drive it thought is was awesome (used to nitro).

It's looking promising.

I'll try to get hold of Paul and see if he'll do anything for me. Especially now that I see the Pro version works just fine (heat plate removed also). I know it was a software glitch/problem of some sort that caused it to go into a stopped cogging state.

[campbellspurloc]

What I meant is that it will overheat. I think that Gordon's test today proved my point. 175deg is on the edge of damaging the magnets. The magnets are only good to 180deg, so you have to ask yourself a couple of questions
1) When did you temp it, after you walked back to the pit, or right as you pulled it off the track.
2) How accurate is your temp gun. To have a 5 degree variance in a temp gun is not that uncommon.

I'd say that it is a realistic assumption that the motor might have reached 180deg. This is what my testing proved when I was running that motor. That is why I said it would not work for 10min plus heats. less than 10min, I know it should make it if properly geared.

As for the performance of the motor, you will see in my post that I never questioned it. I know that the motor will be competitive, just won't last in a long main.

Not trying to pick a fight with anyone, just trying to give real answers to everyone based off the 100+hours of track testing I have done. I have got bad recommendations off the forums in the past, and I am just trying to help people get accurate answers to their questions so that they don't spend needless money on products that don't fit their needs. :)

Campbell

[campbellspurloc]

I'm redoing the chassis on my buggy. Going back to the stock one, with a custom motor/diff mount (as usual). This time I'm able to use a diff because I finally broke down and paid $22 for a single 16mm drill bit. The motor/diff mount is finished, but I still need to cut out a top plate, and then I need that plastic Kyosho plastic spur gear (suppose I should order it soon). I also need to cut out some battery trays from the plate of G10 garolite that I got.

So, I should be able to make it out there the weekend after this coming weekend (damn AP tests!) and be able to run my buggy again. Then, our infamous 1/8 buggy motor/controller tester can have at it!

BTW, anyone want to buy a brand new (from BK directly) Warrior 9920 for $180 shipped?

Travis,
Call me before you go and I will meet you at the track. I have been beta testing Quark controllers with Frank from Quark. He was ripping up the track this weekend with the Hyper 8 we made. You won't believe how good this controller works. I will let you try it when you come out.

[tcolesen]

Will do!

[GordonFreeman]

Race Report:

I just made the tail of A-main at The Rock Pile yesterday! First time racing an 1/8 scale, first time racing at that track.

After the 4 minute warm up and a 15 minute main, the motor and ESC were both in the 150F range. I think we had temp'ed it during practice up to 170F. So I guess it might be getting close to the limit. I might add another fan to the motor/ESC. The hottest part of the motor seems to be the rear endbell. You can touch it but holding it for a long time is not comfortable.

Overall gearing is about 13:1.

After warmup and 5 minute heats, I was only putting back in about 2000 mAhs!!

I was having driver/chassis problems on part of the track so I couldn't push it as hard as I wanted to. But I had the A-main winner drive it afterwards (after 4+15 minutes +1100 mAh back in) for about 5 minutes. He said he could have gone faster with MY buggy!! It looks like it would take about 25 minutes at race-pace to drain the 8800 mAh battery.

Oh, and another note. I used my "old" (1.07) Genesis Pro (not Truck) and it worked great! I had previously removed the "thermal plate" from it also, and have it bonded to a heatsink. And Paul, from Mtronics, told me to send back the 1.05 Truck ESC to see if he could do anything for me on it. After thrashing the 1.07 Pro, I'm sure the 1.05 Truck had bad software/firmware.

Alot of the Nitro guys were very impressed with it's performance. Sweet!

[campbellspurloc]

Gordon,
Glad to see it is working for you. Let me ask you a few questions.
What spur?
what pinion?
did you have a fan on the motor during the race?
did you have a fan on the esc during the race?

[GordonFreeman]

49
12
Yes
Yes

Just the single fan in the picture sort of blowing on the side of the motor and getting some air under the ESC. I was thinking I might add another above and to the other other side of the motor. The body has the normal cutouts for a Nitro motor.

I have about 2-3 hours on the spur/pinion and they are starting to look pretty bad and are quite loud. I think I got the pinion from Starluck and it's an Ofna spur. The pinion doesn't seem very hard. Are there sources for 5mm mod1 pinions that are hardened?

If the outside of the motor can is 160F would not the magnet inside on the rotor be cooler? Since the windings are conducting to the can. Or maybe the whole thing reaches steady state after 10 mintues or so.

[Rtsbasic]

I think it would be safe to assume the rotor would be hotter since thats where the heat is coming from?

To be honest I'm impressed the Mtroniks Pro is working with that setup. Sounds like a nice setup.

I told you Paul was a reasonable bloke :)

[tcolesen]

RC-Monster is currently selling hardened 5mm mod1 pinions. Non-hardened pinions generally shouldn't be used with metal spur gears, but should be fine with plastic gears.

I've measured somewhat of the rotor's temperature after a run by the pinion gear, and found it to be about 5 degrees warmer than the motor's can (heatsink). However, it is possible that some of the heat came from friction between the spur/pinion gears.

[TimisTim]

Well Gordon you have convinced me to buy the Mtroniks pro for my 1/10 ST, already have the truck in my MT2 and love it. I just had my UF75 go out on me again (my fault, I was running it at full speed in front of my friends car with us chasing it and the connectors got so hot they unsoldered themselves, 3.5mm gold's). Blew a motor phase. After hearing your testimonial I bought one to hold me over while the UF is in the shop. It was really a toss up between the Quark 80 and the pro, but I just love the customer support and waterproof case of the pro.

[GordonFreeman]

If at all possible make sure you get the 1.07 or above. I bought my Pro directly from Mtroniks about 6 months ago and got the 1.07. But I bought the Truck version about 3 months ago from a domestic supplier and got the 1.05.

[TimisTim]

Yeah my truck is already the 1.07 but I didnt have much say on the pro. I didnt know you could buy directly from Mtroniks. How is their pricing compared to domestics.

[GordonFreeman]

I think they are still using pounds (rebels ;)) so add about 50% to thier prices. Although Paul did offer me a discount on the pro, since I was actually looking at the sport at the time.

If Starluck can confirm what versions he has, I think it is cheaper buy from him.

[tog435]

I just ordered a Truck from Starluck two weeks ago, got it last week, and it was 1.07... Not sure about the Pro and Sport, but :P

[campbellspurloc]

49
12
Yes
Yes

Just the single fan in the picture sort of blowing on the side of the motor and getting some air under the ESC. I was thinking I might add another above and to the other other side of the motor. The body has the normal cutouts for a Nitro motor.

I have about 2-3 hours on the spur/pinion and they are starting to look pretty bad and are quite loud. I think I got the pinion from Starluck and it's an Ofna spur. The pinion doesn't seem very hard. Are there sources for 5mm mod1 pinions that are hardened?

If the outside of the motor can is 160F would not the magnet inside on the rotor be cooler? Since the windings are conducting to the can. Or maybe the whole thing reaches steady state after 10 mintues or so.

Thanks for the answers. In regards to the motor heat inside versus outside, the motor is always hotter inside than outside. If you were 160 outside, you were probably at least 10-20 hotter inside.

I think you are doing a great job getting that motor to push past its limits with the fan. I am amazed you were able to run that long, obviously the fan is doing a good job at keeping it cool, but be careful because if the fan stops you might have a bad deal. I only say this because I have had quite a few fans get damaged in my testing. luckily I have been running the Telemetry system so I can keep an eye on the temp while I run, so I haven't had any damage. I think if you try a separate fan for the ESC and motor, you might do even better as you suggested.
Good luck.

[starluckrc]

All current stock is V1.07.

Feigao originally rated magnets to 100C (210F). Recent data says 150C.......not sure if I believe that.

[TimisTim]

Good to hear since I ordered form you ;).

Wow that is pretty high temps. What celcius temp does solder flow at?

[campbellspurloc]

All current stock is V1.07.

Feigao originally rated magnets to 100C (210F). Recent data says 150C.......not sure if I believe that.

Keep in mind that if the magnets are rated @ 210, then what temp would the outside of the can be? My guess would be somewhere in the neighborhood of 180. That is why 180 is generally reffered to as a number that you don't want to exceed.

[GordonFreeman]

Update:

Rear end bell came loose on motor. It was like the can (male thread) got beat up and crushed in a bit because the end bell wouldn't stay on and was pretty loose. JB weld seems to have fixed the problem.

Found a nice Ofna gear that fits perfectly around the diff housing (to center it) and bolts nicely to the remnants of the original spur.

Waiting for my Century pinions to try.

Race update:

WooHoo! Came in 3rd behind a former 1/12 scale champion who runs a hobby store in Milwaukee now (hint, hint) and a very good local driver. There were about 18 1/8 scale racers there. I'm stoked!

Not having to pit definitly got me a few positions during the 15 minute race.

[starluckrc]

Good job. I've found the endbell set screw pretty worthless. I recommend attaching it with blue loctite so that it is still removeable if need be.

[GordonFreeman]

Got a new 1.07 Truck ESC back from Paul at Mtroniks today. Heck of a guy. But I guess I won't pull the heat plate off this time.