Arrma Senton Mega Upgrades For Special Use Case

[D1200]

I just bought an Arrma Senton Mega the other day, charged the battery, adjusted the trim pots, and drove it around my house for a little while and its great, but now I want to upgrade it. The reason for the immediate upgrade is I want longevity and reliability out of this unit, because its going to carrying a LiDAR unit around and additional processing, and its going to do lots of driving. I have had a few RC cars before, quite a while ago now, and smaller units then this so I don't have a ton of experience with these. I have been building and flying drones for fun and industrial use for awhile now so I do have some understanding of what I am trying to do, but how much carries over to this I am not sure.

My goals are for this are;
- Convert to 4S (some of the payload has a 4S requirement)
- Convert to brushless motor and ESC (brushes in brushed motors wear out too quickly)
- Upgrade drivetrain accordingly as well

I think I probably want a motor around 2000kv, something like this;

https://hobbyking.com/en_us/turnigy-xk3674-1900kv-brushless-inrunner.html?wrh_pdp=2

But I am not sure if this will fit (diameter, length, shaft size). Inrunner motor sizing seems less consistent then Outrunners, I am used to the four digit number being the stator size in mm for outrunners (ex/ 4213 - 42mm diameter by 13mm long) but this doesn't always seem to hold true with inrunners, for the rotor or the can. If it does fit though it comes in a variety of KVs, as low as 1400 and as high as 2600 I think, roughly. If you have a recommendation for KV to keep the speed similar to stock at 4S that is appreciated (faster is fine, I can limit speed in software, but I don't need it winning any races). I can pick an appropriate ESC. What other parts of the drivetrain would be recommended to be upgraded in these when going brushless? I assume pinion and spur gears? Driveshaft? I bought this because is said the diffs were brushless ready so I assume they good?

As a side note, since I plan to upgrade a bunch of stuff, I will have stock parts I don't need that are brand new I can sell if anyone needs them, including motor, ESC, receiver and radio, battery and charger.

 

[SrC]

I can tell you are a drone guy. Out-runners are drone/plane motors. doesn't exist in 99.9% of surface RC. All surface motors are In runners. With one exception with Crawlers ( think Holmes Hobby motor) Running Lidar equipment can be heavy I guess. You want torque. Brushed motors require more maintenance and periodic brush replacements. Not tragic and not too often as you think. Motors are cheaper. And Brushed has better low end control. But if you want 4s, yes a BLX motor has to be used. 3S is the max for brushed motors. If going BLX watch going too high with KV. 1900 kv and low gearing will be needed for weight considerations. Perhaps a sensored ESC and sensored BLX motor is better suited for your purposes. Will it be used in wet inclement weather? What average speeds and weight will you be running. What run times are you expecting? Will this a be an autonomous controlled vehicle? BLX motors still need to be maintained especially if they get wet. You may want SS Ball bearings throughout if in the wet.
Got me curious.

 

[D1200]

Yeah that was why I was having a hard time comparing them. I know inrunners have less poles, higher rpms, higher KVs then outrunners, but the sizing convention seems different, I also didn't have much reference of what KV is needed for surface stuff, I just knew lower is better. Sounds like I am in the right direction though. The LiDAR and additional equipment are 500g max, not a tremendous amount of additional weight. Inclement weather? Uhhhh, mining, that's the conditions it needs to handle. Its just a test bed, my personal test bed, but it will need to endure some dust, some rocks, some water (usually acidic). I mean it shouldn't get totally dunked or anything but we had another we used at work and the brushed motor did not survive long at all, but someone converted it to brushless and it worked wonders for a long time. I forget what that unit was, not Arrma (Maybe Traxxas?), but it had some other flaws that led to its eventual demise, but this Senton seems to have those licked though. It will probably start walking speed, but I mean if I can get it to work well at the speed it does stock at full throttle I would be mighty impressed with myself. I would like to have flexibility in the speed. It is going to be autonomous, but I always put a CrossFire receiver on anything and I can take control at anytime. SS ball bearings are probably a good idea, was thinking of changing all the fasteners I could reasonably find to SS as well.