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View Full Version : Got a Mamba: Have questions



WeatherB
10-07-2005, 02:52 PM
Hey guys,
I finally broke down yesterday and bought the Mamba Compeition X package with an RC18 12-teeth pinion. I installed a heatsink on the motor and ESC and have these questions:

1. How hot is too hot for the ESC and motor? I was running it in my house (without the body) and after about 5 minutes of running it not too hard it was around 150° for both the ESC and motor

2. When I come to start off from a dead standstill the car hesitates and I can hear the ESC doing something. Sounds like maybe the current protection is kicking in? I have to start off very slowly, but once it gets going there is no problem. I am running the Mamba with all the default settings.

Thanks

P.S. Here are some pics

EphiDelt490
10-07-2005, 03:46 PM
What type of batteries are you running in the car? Good quality batteries will make some of the cogging go away. Also, set your initial power (whatever setup #5 is) to High, as mine would cog horribly when on the stock low. It still does it a little, but I think mainly because I run cheapo batteries that I made out of old cells. Make sure everything in your drivetrain is working properly as well, any binding will heat the motor up super fast. Hottest my motor ever got when I ran it was around 170-180 degrees, and that's after a full pack.

WeatherB
10-07-2005, 03:56 PM
I'm running brand new GMAXX 1200 8-cell battery pack. Thanks for that setting change, I'll do it.

It's raining outside so I'll need to check the temps tomorrow after running outside. What would you say is the absolute max temps for the ESC and motor?

EphiDelt490
10-07-2005, 05:54 PM
Hmm... I don't know. I would say very low 200's at the absolute max. Email castle creations and ask them, as they will definitely know the answer :).

WeatherB
10-07-2005, 06:12 PM
:) I'll do that

The drivetrain is very smooth and both items have heatsinks on them so shouldn't run too hot. I'll try running it outside when the weather clears to get a better idea of the temps.

EphiDelt490
10-07-2005, 07:03 PM
Cool deal. Let me know what CC tells you, as I'm curious.

WeatherB
10-07-2005, 10:36 PM
Hey,
I increased the starting power to High (setting #5) and although the cogging is better it still isn't good enough, I don't think it would have enough starting power to actually make it up a steep dirt hill.

Do I think I should increase the timing from Normal to Race for increased power?

WeatherB
10-07-2005, 10:44 PM
If it helps, the car is 898grams ready to run.

Trickpatrick
10-07-2005, 11:20 PM
I have had the comp x for a few days and I have to say its a dog in the half 8
I have tried all and the timing wont work it just puts the power band up even higher on # 5 set at 3 that helps a little but its pretty sad I think as has been said here already it just does not have the tourqe that the half8 needs period.
If you use a 10 tooth pinoin it is better but still to slow on the start and then the high end is lower due to the lower gear so it just isnt right for it.
I now will have to get AON for sure tourqe is first in this car. ;(

I'll just say it dont.... get the comp X for this car..



Trick

k_bojar
10-08-2005, 12:39 AM
I'll just say it dont.... get the comp X for this car..

Dude, you have got to be the only person with this problem...Don't go bad-mouthing a combo or the half8 without asking for help...

I'm putting a 6800 in my half8 and from everyone I know that races the buggy, that's too much motor.....

WeatherB
10-08-2005, 01:42 AM
I never heard anyone else having any major problems running the mamba in the Mini Inferno other than heat issues so I was disappointed to find out these problems.

Don't get me wrong, it is still way better than the brushed motor, just have to make sure you accelerate slowly from a stand still.

BitHed
10-08-2005, 01:47 AM
...i have to agree though K_B...The MAMBA series doesnt really seem SUITED to the H8...The majority of users of a MAMBA for THIS platform seem to have problems of some sort...

WeatherB
10-08-2005, 01:58 AM
LOL, great... My research didn't really uncover this problem.

Trickpatrick
10-08-2005, 05:04 AM
To All

I did not mean to refer that Mamba products are bad in any way!!

The 8000v mototr is just fine and personaly it never got as hot as I have heard here.

This is my personal opinion with 25 years of playing with rc cars.

The Half 8 needs a torque motor and the compX setup is a low torque high rpm motor not suited for the half 8.

This is not news it has been said here already.
Sometimes we all fall for the idea that if something has a bigger number it some how is better or faster.

The Half 8 is a bit heavier and has more geartrain that hold's the car back a bit sooo. a motor that is stronger meaning more torque is needed.

It would seem that would be in this case to be the AON 4900... becase it has lots of torque or strength to get it moving quicker.

In the real world torque beats horspower most of the time.

Sorry again if I have came on to strong I am frustrated about not getting the 4900 in the first place.
Trick

BitHed
10-08-2005, 05:14 AM
...No worries TrickyP...we knew what you meant...NOW would you go and get the AON 4900 please ;) I know what you mean though by getting / doing something different and then eventually coming back to the original option...Like spending 10 minutes looking for something better than the movie you just watched half an hour of, find nothing, and then coming back to the movie to find that you missed the bit where you find out who the killer is :mad:

Trickpatrick
10-08-2005, 05:29 AM
Exactly!!!!!!

Ever buy something for your car becase it was there and you couldn't get what you wanted so you bought what was close.??

Oh well I have the mamba speedcontrol just need the motor.

Heres a thought. Since you obviously think like I do.

I will be racing on a small indoor dirt track. And I think traction may be an issue.. So maybe the 8000v will work becase it cant take off fast but builds speed with the 10 tooth in probably plenty of speed for a 40 foot straight.
Races will be around 5 min so heat is not an issue.

Cant try till track is in but it might just work. I will try as an option.
I will report back on it soon.

Trick

halfeight0to60
10-08-2005, 05:50 PM
I don’t know about others on this forum but I have a 6800kv in my H8 with no problems at all. When I first got it in it did cog a bit but then with the high start setting, all is fine. If I give it full throttle from a stand still on an unprepared paved road it will spin the tires and gooooo. Maybe if you keep messing with it using all the suggestions on the board you can get it to its full potential

halfeight0to60
10-08-2005, 05:56 PM
BTW Im using a team associated 13t pinion, 8-cell intellect pack with deans plugs and bearings in the hubs (helps a lot incase you didn’t know). Also I have stuck on a few 3-racing alum parts hear and there so I know its not the lightest H8 in the world.

WeatherB
10-08-2005, 07:23 PM
I have the bearings as well and a 12tooth pinion with a very smooth drivetrain.

My 6800 has cogging problems, not sure how come yours doesn't with a 13.

halfeight0to60
10-09-2005, 05:02 AM
Well the only other thing that I’ve noticed just from trial and error is that the castle creations speed control really interferes with my radio if I have it anywhere close to the rx. Even though it was rx interference it acted like cogging. So maybe change the location of your speed control see what happens. It took me awhile to figure this out cause it wasn’t bad enough to show in the steering, the speed control is just really sensitive to the rx inputs.

WeatherB
10-09-2005, 02:34 PM
I'm running Spektrum so it doesn't really glitch. Also, there is about an inch to 1.5 inches of space between the ESC and my received.

WeatherB
10-09-2005, 05:05 PM
Alright, ran the car outside today and the temps were okay except for one time.

The hottest the motor got was 198 on the heatsink and 180 on the can. The ESC got to around 150ish.

This one time the car got stuck in long grass so I was trying to get it out but it kept cogging so after I manually removed it the temps were really high. 230 at the motor heatsink, 200 at the can and 171 at the ESC heatsink. Note to self - cogging causes a heat-up in the motor and esc

I installed another heatsink so the entire surface of the can is heatsinks now. Should help keep things cooler.

WeatherB
10-09-2005, 09:17 PM
Good news... I read somewhere that cogging can be caused by using wires that are too thin. I was previously using 20 gauge wires for my battery pack so I changed it over to 16 gauge and the cogging did improve. It's still not 100% but it's better. :)

mat3833
10-09-2005, 09:19 PM
i would run 14 or 13 gauge. 16 is ok but i use 13. hope you have fun w/ the H8

Matt

WeatherB
10-11-2005, 10:50 PM
Got a reply from CC about the Mamba temps:

The max operating temp of the motor is 200F. The max temp of the
controller is the melting point of solder...300F+. :-) Please let me
know if you have any other questions.

mat3833
10-12-2005, 12:54 AM
hey has anyone used a cooling fan? i got this one: http://cgi.ebay.com/Cooling-Fan-Novak-Tekin-LRP-JR-Futaba-Airtronics-ESC_W0QQitemZ6005417556QQcategoryZ34063QQssPageNam eZWDVWQQrdZ1QQcmdZViewItem it was 5.00 so i couldnt pass it up. oh and how should i mount it. and one more, do i need heatsinks on the motor now? thanks

Matt

BitHed
10-12-2005, 12:59 AM
Got a reply from CC about the Mamba temps:

The max operating temp of the motor is 200F. The max temp of the
controller is the melting point of solder...300F+. :-) Please let me
know if you have any other questions.

...Fot those of us who are metric ;)

http://www.onlineconversion.com/temperature.htm tells me the following temperatures...

200 degree Fahrenheit = 93.33 degrees Celsius; thats not bad, my XSPEED went WAY over that..lol...

300 degree Fahrenheit = 148.89 degree Celsius; thats getting a little spicy :eek:

mat3833
10-12-2005, 01:02 AM
ok
#1 what is the best receiver (besides spectrum im not rich) to use on the H8.
#2 i am using the 5400 and i love it so far(2 batts) it got a little hot w/o cooling holes or heatsinks but i have a cooling fan on the way.
#3 what heatsink should i get if i get one?

Matt

BitHed
10-12-2005, 01:13 AM
#1 what is the best receiver? Doesnt matter...Everything works great...Stay within your budget and work up...If you progress to a different reciever thats fine...I persoanlly use the 18T stock one because its small...If i switch to FM then i will probbaly get a NOVAL XXL...I might just get the AM one anyway...

#3 what heatsink should i get if i get one? Get One that fits the MAMBA...3R does some tall finned ones that will fit, I use 3R short finned ones for the MiniQuake from Dinball...You could get the mamba one which would cover all your bases...if you are getting fan try and get the heat sink that HOLDS the fan...

WeatherB
10-12-2005, 01:59 AM
I don't think you need a fan... I mounted a heatsink on the motor / ESC and the max temps have been about 180 so far after an entire battery pack of running.

Considering how CC said the ESC can run up to about 300° be more worried about covering the entire surface of the motor with heatsinks.

BitHed
10-12-2005, 02:46 AM
...have to agree...I feel a fan is overkill...go heatsinks :)

mat3833
10-12-2005, 03:38 PM
man if i had that info yesterday... i have it on the way already. i got the idea off regan. o well. ok i have a realy old and realy big futaba receiver. it takes up my whole receiver tray thing. i have to find a spot to mount my ESC. i tried putting it on top of the receiver, BAD IDEA!! the car turned on, shot down the driveway, hit a pothole/jump and launched into the air :eek: . about 4 tumbles a slide and 30 ft later it came to rest. it drove away but it was my first real scare. i was looking at a novak receiver but i dont have the money. i need a small 75mhz FM receiver to replace my beast. i will give a report on the fan when i get it. man i will be ice cold!!

Matt