Tsubaki

I've been running nitro cars for a few months now, and I wanted an electric so I got myself a Associated TC4 kit.
All I need now are batteries and ESC/motor.

I'm pretty sure I want to go brushless but I also want to be sure I am ROAR legal in case I get into racing later.

I looked at Novak systems (the 5.5 in particular) but I hear of overheating and glitching issues. Now, this could be operator error with gearing and they do say that the ESC being too close to the Rx will do funny things but I want to know what the concensus is with Novak quality.

The next thing is sensor Vs sensorless; everyone RAVES about Mamba Max but it isn't ROAR legal, or atleast the motor isn't because of its wind? I love the fact the ESC is so tunable but can I take a sensorless motor from say, Trinity that is Y- wound (ROAR legal)stick it on a Castle ESC and make it work?

So just from searching the forums for the last 2 hrs, should I go with a Catsle ESC and a ROAR legal sensorless motor?
Also, can cogging be eliminated by using good batteries and lower gearing to keep the revs up?
Is there a better alternative that won't cost me an arm and a leg?

Thanks!

Ken

RURC

If you are going to go racing as soon as you get the car together then you have no real choice but to go Novak or LRP (please read further). Both of which are quality systems that have all the problems you stated. However even thought they are quality ( I have to say this because too many people cry when I dont) they suck when compared to almost any sensorless system out. Let alone the Mamba Max.

Let me stop here and tell you that I have them all and many other brushless systems. Hacker, MGM, BK, Quark, Novak, LRP, Mamba, and Align. The MTronics is on the way but not here yet. I use nothing but brushless now. I have been in this sport (I hate calling it a hobby) for almost 30 years. I have ran the full gamete of cars. I do know of what I speak.

There are many factors that make a brushless system good or bad. Versatility being one of the most important. The Mamba is crazy adjustable. You adjust it on your computer through a USB connection. I keep asking for blue tooth but they have not done it yet. Since ROAR dose not sanction ESC's you can even use the Mamba in the stock class with the right brushed motor. Yes the Mamba is also brushed compatible controller. It has no motor limit. So you can use it everywhere and still have the adjustability. You can then get the Trinity or what ever motor comes out that gets the ROAR stamp of approval and goto town. The system will have tons more power than either the Novak or the LRP. Both of which's motors produce less than 400 watts peak and the Mamba will run 1000 watts all day long.

Sensorless and sensored. Here is the thing the only reason sensored motors exist is that the initial acceleration feels more like a brushed motor. This gave slightly smoother starts and slightly better feel again out of corners. The real effect is minimal at best to me. But many that have been brought up on brushed motors swear by it. My son has never used a brushed motor. Only sensorless brushless motors. So the effect here is that he dose not need the feel of a brushed motor. He has never known it. He will be at the track as soon as Trinitys motors get the approval stamp with their motors and a Castle controller. He is 7. With the programming getting better and better on the sensorless systems the problem of cogging is almost nonexistent now. If you have never used a brushed motor I suggest you dont. Brushless technology is going to completely take over the RC industry very soon. It will even take over nitro.

You can run delta and Y winds on any sensorless controller. The reason that ROAR went with Y is that delta winds are expensive and the fastest. Most systems out are Y. If you look at Neu Motors they come both. All the fastest motors are delta.

Cogging can be helped with the gearing but proper gearing is always important. And batteries are extremely important no matter what. YOu have to supply the power. If not nothing works well. The Castle Mamba can be bought ( http://www.b-p-p.com/products.php?cat=40 ) for a little over $200 with motor. Less than $150 just the controller. Looking at the options it is the best overall choice.

I hope this helps

SkrapIron

What RURC posted is correct, but I wanted to expand on the sensor based vs sensorless DC brushless motors a bit.

The biggest advantage a sensor based motor has is it's near elimination of Cogging. Cogging is the result of a combination of supplied voltage fluctuations and an imperfect geometry between the rotor and stator as the winding is energized. It prevents smooth rotor operation and generates unwanted electrical 'noise'.

A sensor based brushless motor employs either a Hall-Effect or optical sensor along with support electronics (based in the ESC). Sensor based motors have, as RURC stated, a smoother feel as you accelerate. This is accomplished using the resident sensors determine the exact position of the rotor inside the stator and allow for the controller to energize the appropriate windings with optimal timing.

Sensorless brushless motors generally control the energization of the stator based on back-emf zero-crossing. The motor's back-emf is generated and determined by the rotors position and speed. Simple resistor based circuitry is used to determine the rotors position based on instances when the back-emf reaches an inactive zero phase. Newer controls take this determination one step further not only by monitoring the back-emf, but also by calculating the rotors exact position with additional current feedback circuitry using the controllers sampling rate.

The motor efficiency then becomes a product of the quality of suplied voltage. Inconsistent voltages are amplified by the impercise nature of the motor timing when using a sensorless-system. It is therefore crucial that the motor is supplied with the best current possible. This is achieved using high-quality batteries, low resistance (or zero-loss) connectors and good solder joints.

In application, a sensorless motor can reach higher rotational velocities than sensor-based motors. This limitation is due the the processing time required by the sensor an its support circuitry.

I hope I didn't confuse you too much.....

zephar123

One thing I thought was interesting I had a guy helping me out with my buggy who hates brushless motors. I ask em if hes ever driven the mamba and he had not. After he had driven it he was amazed and said it felt more like his low turn brush motor then any other hes driven. Which Ive got the settings setup to give it that feel through the usb, but was interesting whatever it was he did not like abotu the other brushless the mamba had.

btw everything rurc and scrappy said above 100% correct. this was jsut an interesting thing ayesterday as this is same guy that just Won the harvest race with his xx-4

Access

Well brushless has come a long way. I've had similar experiences many times. People that were turned off by the early days of 'cog city' and the heat buildup that caused are turning around b'cos of systems like the mamba maxx. And once the trinitys come out there will be even more converts out there.

RURC

Out of all the cars I have the only one I have any cogging issue with is my converted Schumacher Havoc. I cant get rid of it. Even the Novak jumps once with this thing. Here is where the problem lies I think. The gears. This thing has the biggest spur gear I have ever seen. It has 63 teeth with 16 on the pinion. Now you say 63 thats not that big. Look at one. The gear size Schumacher calls it a 25 pitch. The gear is over 68 mm across. Thats more than 2.6 inches. Its huge. But it is only during start from inital start from dead stop.

SkrapIron

RURC,

Are you still running the multi-speed transmission, or did you lock out all but one gear? If you're not starting out in first gear, you're probably experienceing a condition called torque cogging. Starting in anything but first would put sufficient stall torque on almost any motor and would cause the problems you are describing.

RURC

NO multispeed. It is not even an option on the Havoc.

SkrapIron

A single speed transmission, in something that heavy? I can see it causing problems like you described..

Any idea what the transmission ratio is for that truck?

RURC

I will get you the weight on it. It is not that bad. A little heavier than one of my 1/8 buggies. Like I said that gear is HUGE. It is the only one I have a problem with. But all my speed controlles have a problem to varing degrees with that one, even the sensored ones. I live with it. I just dont stop. LOL

PS I will get the ratio also for you.

-Inverted-

From my experiences the Quarks tend not to cog.

For the thread starter,

One thing to consider before you purchase a electronics setup is what batteries you will be using. It doesn't matter if you have the best brushless system money can buy if your batteries cannot supply enough amps to power the thing. Think of it in a computers term, it doesn't matter if you have the fastest processor if your only running 256 megabites of Read Only Memory (RAM). If your local track allows it I would reccomend lithium polymer. I have learned to love it and will never go back to another ni-mh pack again. However if your local track doesn't allow it at least do yourself a favor and purchase some quality Ni-Mh packs. Gold Point (GP) and Intellect Batteries (IB) are the top two currently on the market. I would reccomend the 4300 GP or the 4200 IB packs. A zapped pack occurs when a machine is used to "zap" the pack with a selected voltage rate to lower the internal resistence, therefor producing better performance. Matched batteries are cells grouped by voltage and other characteristics to allow more equal performance throughout the entire pack. If budget allows definately pick up some matched and zapped packs. As far as the old sensored VS sensorless debate, I feel sensorless has developed to the point where the cogging had reduced dramatically compared to the older sensorless technology.

-Inv-

RURC

Vert- Its me man RURC (Michael). I know you are trying to help but now I feel bad. LOL. I only use top line lipo cells from Thunder Power, Max Amps, and Apogee. When I make my own Max Amps supplies my cells. I have had the most consistent voltage under load from Max Amps then anybody. 6000 to 8000 mah with 20 c rateing in 11.1 and 14.8 configurations. Sometimes upto 22.2 volts. But that inital cog is there. I have never had a brushless controller work flawless in that truck. I have used Quark, BK, MGM, Castle, NovakHV, heck I even put in a Hacker Master Car for good measure. I am really not too concerned about it. I am really not sure why I mentioned it. Oh yea someone mentioned how cogging could be a problem. Like I stated it only happens from dead stopped and then if you try to do a fairly easy take off. It is less than 1/2 second. The problem if you hammer it from dead stopped................ it generally flips over onto its back. I love that truck. Even with the cogging.

ftt4maniac

You guys have opened my eyes to mamba. What i would like to know is, does brushless, when timed, have the same affect as a brushed motor. Overheating, wear out quicker, kill battery life. I have a novak 6.5 and i am getting about 30 minutes of run time out of it with matched 3300's. I think that is awesome. You say mamba will blow novak away, you got my attention, but how is battery life compared to novak.

RURC

If you do the same conditions you will get about the same kind of time. The efficiency of the Mamba system over the Novak is a lot. Now the Novak tops out at around 300 watts and the Mamba will do continous running at 1000. But the times will be close. The Novak will most likely get a little better. But you will get there faster with the Mamba.
As far as batteries if you dont use very good batteried you will greatly reduce their life. I was waiting for my lipo cells to get in for my Mini Inferno and I made a 9 volt pack with intelect cells. The set up in the car was a Align 35 amp controller and a Hyperion 6000 /volt motor. The pack lasted about 10 charges then it was trash

ftt4maniac

Thanks rurc.

RURC

I am very glad to have helped you.

Tsubaki

I would like a big thank you to everyone for all the great advice.
It made my decision really easy, I went with a Mamba combo.

Next up batteries!
Will IB 4200s cut it?

zephar123

well Im running IB 3300 and as long as power is set on low your ok, but any higher and need to go with lipoly. Also tuiming set to normal. If uou set it to higher power it will damage the battery, but I seem have plently of power on my 5700

Tsubaki

Ok then, how does battery life relate to power settings or motor power.

I'm guessing if you try to draw more current than the battery can supply you end up damaging the batteries.

I intend on going NiMh, if so is there a better alternative to the IB batteries? Recommended vendor?

rcxboy

Well, GP make great cells as well.

boomboombatteries.com make great IB packs, theres an RCU review on them..

RURC

All the top batteries are very good. Just dont get cheap batteries. If you rea.lly want to open up your Mamba get some lipos. The jump is amazing.

zephar123

I think Ib makes the best NIMH, I to use NIMH and they run fine and got tons of power in my 5700. Heck I dont want any more power be honest the track I race on that adobe crap dirt its slipery. 1/8th scale guys slip and slide.I would buy a like you said a 4800 MAH make sure its not a stick pack and what ever you do make sure to use ultra deans plugs.

If you draw tomany amp[s fromt he battery what will happen is the batter will get to hot.

also if want that extra juice get match packs, although if getting liek the boom boom batteries I would not worry about it and boom boom makes good packs.

hmm looks like boom boom still out of batteries ill look today and show you links to some good batterys. DOAH! whats up with boom sayign out of stock are they really out?

RURC

Goto Max Amps .com Those guys crank. They have it all in stock and a great selection of LIPO.

ftt4maniac

Rurc is not kidding, i just checked that website out. Awesome. 12000 mah lipo 7.4 volt, thats insane.

RURC

I have one of the 12000. It is thicker than a nicd but if you got he room, hang on for a long time. I have 6 lipos from them. They all work flawless. I have 3 2 cell 4000 mah, 1 3 cell 4000 mah, 1 2 cell at 12000 mah, and a 3 cell 2200 mah 3s2p saddle pack for my Mini Inferno. They build all packs here in the states. They can custom anything. They do NiCd and NiMH but I havent used those in about 4 years at all. The Mini Inferno pack was a custom for me they did not know there was a need. They made it and it is fantastic. They are my supplier of choice.