Senton Arrma 4S or 6S motor in a stock Senton 3S V2

[K-BASH]

Alot of factors come into play.speedrunning pulls some juice.bashing not so much.my record so far mmx8s pulled 385amps on a pass

 

[TimePancake]

Went for one of these at 2650KV:

https://uk.banggood.com/Surpass-Hob....html?cur_warehouse=CN&ID=516955&rmmds=search

I 'think' the stock pinion in the Senton is 20T so I'll probably order up a 23T 5mm pinion for this one and see how I get on.

This looks such good value, I was looking to replace the bearings in my 3660 for ceramic hybrid and that will cost the same...
Tbh I'm very very sceptical about buying from 'bangcrap' so I'll be keen to see how you get on

 

[iep]

Okay, the results are in. Bangood played a blinder and got the motor to me in 8 days. It then took me a while to get around to installing but we're there now.

I fitted the Surpass 3670 2650KV motor with a 20T pinion (vs original 3200KV motor with 20T pinion). In theory this would give me a 2650/3200KV reduction in top speed (about 17% loss) but I was hoping for a bit more punch.

Well, the motor is terrific. The car is completely transformed. The accelration across the whole speed band is hugely improved and, in the relatively confined space I was driving, I noticed very little reduction in top end speed. I'm guessing the extra torque means the motor gets closer to its maximum RPM than the 3200KV one was able to.

As a bonus, the brakes are now far stronger too (makes sense). Without changing any ESC settings, the car has gone from 'normal' braking to being able to front flip when I hit the brakes hard.

I only managed a 5 minute blast but after some full throttle driving both the motor and ESC were only warm to touch.

My only concern now is what all this extra torque will do the drive train.... My guess is that the diffs should hold up (since they are commn to the 4S platforms) but I'm a bit concerend about the stock spur gear. Time will tell.

Thanks to @K_BASH for the idea. I would otherwise have blown a ton of cash on a new ESC for limitted benfit. Bearing in mind the spend here (£18 delivered) the motor is a total bargain.

I can't comment on reliability yet but the bearing etc on the motor seemed decent enough as did assembly fit/finish. I'll report back if I have any issues.

 

[TimePancake]

That's great to hear! And a real bargain to boot. I've had my finger on the trigger for since your last post but couldn't decide to spend it on a top quality bearing or the full motor.

 

[studawg]

I went with a similar Surpass motor, but it's on the slow boat from China. I purchased a heatsink / fan combo I plan to use with it so the temps sound promising.

 

[iep]

There are a lot of variables in this but, as I understand it, the lower KV motor has a higher resistance. So, in theory, run on the same voltage it should draw less current. This should mean the motor anfd ESC running cooler than stock. This appears to be true from a quick test.

That said, nothing comes for free so where am I getting all this extra power?

Conclusion: I don't adequately understand motors...

 

[Jerry-rigged]

At the same voltage, the new motor will make less RPM. But the longer shaft means a LOT more torque, so you can gear it up. Total power is higher, wattage is higher, so amp draw is higher.

 

[iep]

Makes sense. Only point here is that the motor is not geared up so is working 'less hard'. Certainly, the rig as it stands is running cooler than stock.

 

[Jerry-rigged]

Same voltage, same gearing, you should have a noticable lower top.speed? So the motor will not be working as hard, so less heat.

 

[iep]

Yeah, 2650/2300 = ~83%.

So theoretically a bit of a speed decrease. In reality though I'm not noticing it. Maybe just that the acceleration is so much greater now that it just 'feels fast' but I also wonder if the increased torque means the motor is getting closer to is theoretical max RPM than the stock 3200kV does.

 

[iep]

It's been busy so I only managed to take this thing out for a proper bash last night.

As a catch up, didn't use an Arrma motor, went for this banggood special:

https://uk.banggood.com/Surpass-Hob....html?cur_warehouse=CN&ID=516955&rmmds=search

Ran two 6000mah batteries through it in a large area of mowed but pretty long grass (with loads of spots for small jumps/whoops).

Conclusion, this is a huge upgrade on the stock motor. Almost zero cogging even when pulling away in long grass. If it is slower then I'm somehow not noticing. I guess the top speed might be a little reduced but the quantity of torque across the full range is increased so it somehow feels faster.

I think the best feature is that the increased torque means you can really modulate the power even near top speed. Belt along at 80% and then a blip of full power to get the back of the truck to break free and slide (even on dry tarmac). Just far better control.

As to temps, it was a warm day (by Scottish standards) and after two packs in longish grass the motor was very warm but not too hot to touch and the ESC was cooler than that.

Battery seemed to last pretty much the same time as it used to.

I can't speak to reliability or consitency but I'd say it's worth a punt.

 

[BulletRCs_NZ]

This looks such good value, I was looking to replace the bearings in my 3660 for ceramic hybrid and that will cost the same...
Tbh I'm very very sceptical about buying from 'bangcrap' so I'll be keen to see how you get on

I buy off Banggood all the time and apart from the shipping time of 3-4 weeks I've only had good experiences.

I got this Surpass 3660 3300kv motor and it has been great.
https://banggood.app.link/2U1xTjtqihb
Cheaper than replacing the bearings in my stock Spectrum motor. I've ordered the 3800kv varient to see how that goes. At $30NZD to the door why not, so cheap.

 

[dure16]

As a catch up, didn't use an Arrma motor, went for this banggood special:

https://uk.banggood.com/Surpass-Hob....html?cur_warehouse=CN&ID=516955&rmmds=search

Which kV rating did you choose?

 

[iep]

Which kV rating did you choose?

Went for the 2650KV version. As a I say, theoretically only 82% the speed (kept same pinion) but I really couldn't tell.

I guess if speed runs are your thing, you probably need the higher KV. But, IMHO, for general bashing the 'immediacy' of the speed that you get from the torquier motor gives a greater impression of speed.

 

[BulletRCs_NZ]

I could see one of those going really well in my Big Rock with it's 4s capable HW ESC.

 

[iep]

I could see one of those going really well in my Big Rock with it's 4s capable HW ESC.

For 4S, maybe even consider a 4068 can?

In other news, how great is the 4x4 BLX to work on? I mean it's just light years ahead of other manufacturers.

 

[K-BASH]

I could see one of those going really well in my Big Rock with it's 4s capable HW ESC.

4068-2650kv is my favorite 4s motor ive tried in BR.

 

[dure16]

4068-2650kv is my favorite 4s motor ive tried in BR.

Pretty heavy motor compared to stock. Do you notice the extra weight while driving?

 

[Kla912000]

I could see one of those going really well in my Big Rock with it's 4s capable HW ESC.

I have that same Surpass 3670/2650kv motor in my Big Rock. Run it on 4s with a 19t pinion. It has loads of torque and it is stupid fast.

4068-2650kv is my favorite 4s motor ive tried in BR.

That's what I'm gonna try next. Have 3670/2650kv on 4s now.

 

[morrjr71]

I have that same Surpass 3670/2650kv motor in my Big Rock. Run it on 4s with a 19t pinion. It has loads of torque and it is stupid fast.

That's what I'm gonna try next. Have 3670/2650kv on 4s now.

I'm considering changing out the motor in my Typhon 3s. What ESC are you running with the Surpass 3670/2650?