Granite Can the stock brushed motors handle 3S at 50% throttle?

[dure16]

Granite voltage. Aftermarket 2S/3S ESC. Have 3S batteries but I imagine the stock 540 20T would fry on full 3S. I also have a mega 550 12T motor I can use.

Would turning the throttle limit down allow me to use 3S for both/either motor?

 

[SrC]

I have run them on 3s. They will run hot. The brushes will go first. Then the 2 brass Oilite bushings. But brushed motors are real cheap. Maybe worth the performance boost? I run rebuildable brushed motors with Ball bearings and swap out to new brushes as needed. Lube the BB's with a drop of oil after every run. Easy enough. Preventative maintenance goes a long way with any motor.
550 Brushed motors are generally rated for 12v. max. By design. So 2s is more correct. But 3s is right there around 12v.
You can try and measure the ESC-motor voltage output at the 2 motor leads with a DVM and see how many volts 50% gives you. That's a good reference of what you will get. With 50% power. Maybe you can up the power as needed. The motor wont explode on you.
I was never a fan of the Power Limiter on any of the Spektrum radios. Didn't like it with my STX2's (BLX). Just me.
Make sure your ESC can handle 3s. If not it will burn up, just not turn on. Maybe never.

 

[ARRMA King]

I’ve ran a few rtr brush motors at 3s no problems just to see but frankly it was a let down because the added voltage does NOT scale up like a brushless does once your used to brushless scaling.

figure in maybe an added ~25% top end increase.

 

[SrC]

^^^ depends on the gearing. And the brushed motor winding and poles. If you up the voltage, need to drop the gearing down. Brushed motors have a fixed narrow torque band. More so than brushless. Night and day different than BLX.

 

[Yonic]

Well, if there is no curve applied in the remote or the esc and the esc is calibrated correctly, then 50% on the remote should give you half the voltage of the 3s battery at full throttle, meaning around 6v, which is less then a 2s battery. so yes. the motor should be totally fine on 3s with 50%.

100% throttle means the ESC supply the actual battery voltage to the motor.

 

[SrC]

Yeah in a perfect world. That is more of an assumption. I don't feel that is accurate enough. Just use a volt meter at the 2 motor leads and you will know exactly what is going to the motor at any throttle setting. Easier and accurate way to confirm if what you say is correct. I have a DX2E with Thr limt. But I run BLX and there is no way to measure motor output power. I never felt that P. limiter was correct at all. compared 4s and 6s at different settings and it was all over the place. The rig ran so much better at 100% with a 4s braking and all, compared to running 6s at 75%! My V1 Infr.
Thr Lim sucks anyway. Braking response sucks at different Thr. levels etc.
But for the OP's purpose on Brushed it may serve a purpose.

 

[SrC]

Well, if there is no curve applied in the remote or the esc and the esc is calibrated correctly, then 50% on the remote should give you half the voltage of the 3s battery at full throttle, meaning around 6v, which is less then a 2s battery. so yes. the motor should be totally fine on 3s with 50%.

100% throttle means the ESC supply the actual battery voltage to the motor.

+1.
I always run my radio's at 100%. I never liked the response of the Thr limiter on those RTR Spekrum radios. When you change settings dropping down in power, the braking and all seems weird to me. But many guys use it, and have become reliant on it.

Brushed 550 motors seem to perform best with 9.6 volts max. This equates to a 7 cell hump pack, Nim or Nicad pack. OG Brushed motors were never originally designed around and for Lipos. 3s can work however, but just don't expect much life from the Brushes and Commutator. Brushed motors can't handle the RPMS in this case. Never designed for it. But brushed motors are cheap to replace. Don't expect them to last long, like BLX do. BLX motors can last for years and years if maintained well.

 

[Vortex 2wd]

Granite voltage. Aftermarket 2S/3S ESC. Have 3S batteries but I imagine the stock 540 20T would fry on full 3S. I also have a mega 550 12T motor I can use.

Would turning the throttle limit down allow me to use 3S for both/either motor?

I'm trying it at 75 percent. With 3s. Been a day and maybe 40 mins of run time. Few short drive and bash sessions.

Motor never got hot. Doesn't mean it's working. Or won't blow the motor but the difference is wonderful for added power.

I found that half trigger is about full speed of 2s.. or nimh

Full trigger is a lot faster and tons of torque. Also down geared to 14 instead of 15

Maybe I'm finally to where the brushless kind are. Use half power then hit it at the jump and it goes.

Before as you may know it was full power to get speed and hope it hits right.

I'm just having fun.

I'd guess it hits 30 or so. And has like 50 percent more torque. if the motor goes ill drop it back to normal and call it a fun tester for a brushless later

 

[SrC]

When you "Hit", you should not be at full throttle and flat out.
And it is always good to make sure trigger can effectively be used through its whole range. Because only then will you have the "full torque" range for the necessary control at all times. Gearing down to the best ratio is smart. The brushed motor will also last much longer.

 

[Vortex 2wd]

When you "Hit", you should not be at full throttle and flat out.
And it is always good to make sure trigger can effectively be used through its whole range. Because only then will you have the "full torque" range for the necessary control at all times. Gearing down to the best ratio is smart. The brushed motor will also last much longer.

Must be the jumps I use. Most make it nose dive. So holding trigger down makes it land flat

There are 2 where nose stays up and I hit the brake to bring the nose down. But the rest are pretty flat jumps and it will nose dive.

Guess the line up slower and hit it may not be right but seems to work. I think that's what the dude at the track told me to do with his.

What's your advice? I've tried flat out and this idea.

 

[SrC]

It is just common practice to hit the ramp/jump when not at 100% Thr. Because you end up with less rotation control, once you lift off the ramp, the critical part of Big air success. Full speed until just before the ramp is fine. But that moment on the ramp/jump, you want some reserve throttle remaining to control that rotation. Nose diving is sometimes a result of the chassis setup, chassis balance etc. Even shock setup influences this. Many factors to consider. Adapting driver input is just one part of it.