Help which motor Demon rigger on 3s or 2s

[CRSalt]

Need some help figuring out which motor and props work well on an ETTI demon rigger. Any help would be great

[Meniscus]

Welcome to OSE! With any rigger, one of the limiting factors is the size of the ESC, motor and lipos because of the limited space available to fit everything. That being said, a few questions that may help facilitate some good responses to your inquiry:

1. What type of runs are you interested in? Examples may include: sport boating with shorter run times, heat racing for a certain number of laps, rough water running, smooth or glass water, all-out speed for either oval or straight-away (SAW), etc.
2. Do you already have some components that you are considering using in the model such as lipos you already have or an ESC you would like to use?

There are a lot of other questions, but this is a good place to start. The reason why this information is important is to determine what props may be best for your application. For example, if you are running in rough water which may or may not include running with other boats at the same time, you may want a little more outside diameter for the prop. With a larger prop, you will likely want a motor that is a lower kv so that the resulting setup doesn't put needless stress on the components. Conversely, if you only plan to run in very smooth water, you may like a higher kv setup turning a smaller prop. In most cases for sport running, staying away from very high RPM setups will result in a more reliable boat in the long run.

Another thing that is important to mention is that as you go to more cells and voltage, the amperage goes down. In this case, it means that a 2s setup will likely run more amps than a 3s setup. However, you may find it difficult to fit two 3s lipos (for 3s2p) into the model with the other components if you wanted extra run time. At the same time, you may find that you can fit a single, large capacity 3s lipo where you couldn't fit two 2s lipos for 2s2p.

The single most important thing that would be helpful to consider is the ride attitude of the model itself. In other words, making sure that the model has been built with the appropriate Angle of Attack (AOA) for the sponsons is critical to ensure that the components don't incur additional heat/stress or create strange ride attitude issues.

Hopefully this make sense. If you have any questions, please feel free to ask. As indicated, sharing a little more information concerning what you hope to achieve will help everyone provide more meaningful recommendations that will work for your application.

[Meniscus]

I see from another thread that you have provided some of this information which is included here for convenience:

CRSalt wrote: "Hey friends i have many FE boats but this Demon is a Demon. I really would like to know if anyone races or knows some one who races that knows a good motor prop combo that is competitive. I Live in Iowa and they do not race anywhere in my state. I am planning on going to MN to race but have struggled with it. I am getting the batteries too hot. I'm running a 5450kv 3650 size with a 37mm prop. I run a 120 swardfish esc with data logging. I have cut back the prop to get the amp draw back but it is a turd on 2s. Bullet on 3s but the motor leads are reaching 170 deg and the motor connectors are so hot the solder melts and surface temp is over 230. ESC and motor temps are fine."

With this information, do you mind sharing what 37mm prop you are using? There is a big difference between an X437 and a V937/3. Also, what size bullet connectors are you using?

As a side-note, running a 5450kv motor on 3s means that you're running over 60k RPM unloaded. It is very rare to see anyone run that many RPMs on even SAW boats in competition. I'm not saying that it doesn't happen, but we certainly run considerably higher rated ESCs and there are a lot of other concerns such as the heat build-up in the driveline and strut among other things. What does your data logging tell you about those runs?

[NativePaul]

This is a pictorial setup guide from Dee Chan (ETTI's driver and tester, who speaks very little English hence the pictorial guide) Posted on the AStec forum at the time of the Demon's release. There have been a fair few of these racing near me, some with the 5500kv b36s on 2s 5800-6600mAh and more later with Leopard 2860 3400kv on 3s 4000-4500mAh, ESCs are usually 120A, props are in the mid 30mm range and normally either graupner carbon, ETTI CNC, or Tenshock CNC, all of which have less load for the diameter than an an Octura X4xx of the same size. This is for Naviga Hydro1 racing which is what the boat was designed for, whether 2s or 3s the cells are low C rate to get those capacities under the same 280g weight limit, and the races were 5 minutes, + 10second mill, + in lap, speeds were in the mid 40s.

Personally I don't think this boat is really suitable for any of the popular American classes, you wont fit a Pltd setup in it, and it is too small and weak for the speeds of a full on N2 1p setup that would fit. It would probably make a decent N1 or M (I'm not 100% on those class names but 2s stock motor and 1s open motor) boat, but as far as I know nobody races those outside of SAWs and Time Trials anymore.

Hi guys,

Hope you guys enjoy our data..... ^^

[NativePaul]

More setup pics

[NativePaul]

Still more

Hi guys,

[NativePaul]

Even more

Hi guys,

[NativePaul]

Damn the 6 picture per post limit here.

Hi guys,

[NativePaul]

Again

Hi guys,

[NativePaul]

Last few.

Hi guys,