Kagama RTR - ESC BEC Voltage Increase

[PacketLoss]

Apologies for awaking an old thread but it appeared inconclusive: https://www.corallyforum.com/threads/bec-voltage.206/

Im running a stock RTR Kagama, and was tipped to increase the BEC voltage for the benefits mentioned (most notably the servo torque). However having checked the max voltage inputs on the bits that the BEC provides, I notice the RX seems to suggest a maximum 6v input, although it's not explicit, rather inferred from the wiring diagram.

Does anyone know if the Corally R-323 RX supports 7.4v or are already running the ESC with higher voltage without issues?

Cheers!!

 

[KnowAir]

I don't know if it's rated for 7.4v, but I wouldn't be concerned. I don't own a TC radio/receiver, but have put 7.4v to other brands without any issues. If it were to cause the receiver to go out, I'd consider it almost a bonus, as in an excuse to buy something better. My brother has two different versions of the TC radio, the Kronos RTR and Asuga RTR, he doesn't care for either of the radios, claims the Asuga has a very notable delay or lag in response. I drove the Asuga (briefly) but didn't notice it myself. They're bottom of the barrel though, as most rtr radios seem to be.

 

[PacketLoss]

I don't know if it's rated for 7.4v, but I wouldn't be concerned. I don't own a TC radio/receiver, but have put 7.4v to other brands without any issues. If it were to cause the receiver to go out, I'd consider it almost a bonus, as in an excuse to buy something better. My brother has two different versions of the TC radio, the Kronos RTR and Asuga RTR, he doesn't care for either of the radios, claims the Asuga has a very notable delay or lag in response. I drove the Asuga (briefly) but didn't notice it myself. They're bottom of the barrel though, as most rtr radios seem to be.

Thanks for the reply @KnowAir

I accepted long ago, when others talk of control lag I assume they’re under 30 and at my ripe age, I’d not notice

Anyone else?

 

[Shakka Lakka]

Thanks for the reply @KnowAir

I accepted long ago, when others talk of control lag I assume they’re under 30 and at my ripe age, I’d not notice

Anyone else?

I bought the Asuga and tbh I noticed the lag (I'm 34 btw) it's subtle but it's there so I changed the radio and I'm much happier, I have a noob question. Since I've upgraded my radio receiver combo, is the method to change the servo BEC voltage the same even with the new receiver or does my radio override it (Radio Link RC6GS V3)?

 

[razorrc]

I bought the Asuga and tbh I noticed the lag (I'm 34 btw) it's subtle but it's there so I changed the radio and I'm much happier, I have a noob question. Since I've upgraded my radio receiver combo, is the method to change the servo BEC voltage the same even with the new receiver or does my radio override it (Radio Link RC6GS V3)?

There’s no BEC control in the radio/receiver, it’s all done through the ESC.

 

[Shakka Lakka]

There’s no BEC control in the radio/receiver, it’s all done through the ESC.

Awesome thanks, I'll go through the manual and change it

 

[KnowAir]

Thanks for the reply @KnowAir

I accepted long ago, when others talk of control lag I assume they’re under 30 and at my ripe age, I’d not notice

Anyone else?

Well my bro and I are in our fifties.. he's older yet I didn't notice the latency, LOL. In my defense, I only drove the Asuga for a couple minutes.
Also, I use a Flysky GT3b for most of my rigs, which is actually notorious for latency, maybe I'm numb to it? IDK.

 

[Horatio]

I'm quite old, but my reflexes are still decent.

Latency is 100% a thing that you would definitely notice if you were doing a side by side comparison. Even if you're old.

I fly FPV drones. You really want the lowest latency possible, especially if you're flying through gaps etc. Typically my goggles operate with a latency of 28ms. The plus side, I get to see a HD picture with no noise. This seems an acceptable compromise.

With RC cars, if you drive a touring car around a track with a poor radio and slow steering servo - you'll 100% see the difference. The thing is - you still have to put in the right input - lower latency, HRS, FASST etc - it doesn't drive for you. But it will work for you if you're putting in the right inputs. Below 15ms, latency has no impact on human performance.

My FASST 3VCS operates at 11ms latency, which even after 20+ years is still pretty much as good as it gets. Which is why I don't change my radio. That and the fact that they don't make stick radios like that any more.

There's no disadvantages of having a responsive radio. Or one that offers full range - that's really important for bashers that drive in very wide open spaces, or speed runners that run their rigs over 1/4 mile away.

My BEC voltage is often limited by my choice of receivers, but that's because I'm a big fan of Futaba FASST Receivers. They're as rare as Unicorn tears and expensive, so I won't risk magic smoke by using 7.4v instead of 6v.

And for the majority of us - why risk it? More speed and power - but via a high latency, RTR radio? Pointless as tits on a bull!

My choice of Protek and AGF servos work well on 6v. I select the specs based on their 6v performance, generally. Except my Savox on the Baja, which is a comparatively slow servo @0.21s/60° and 30kg of torque at 6 volts, but I still have no intention of running higher voltage because of the Futaba receiver.

Where I use FRSky FASST Receivers, they allow voltages up to 10v, so I could put the Torox 185 to 7.4. - but I generally don't. I conserve the energy for propulsion.

The other thing to consider is the servo saver spring on Corally rigs. If it hasn't been upgraded to a higher rate spring, none of the extra torque & speed from the extra 1.4v is ever going to reach the wheels.

 

[KnowAir]

I couldn't tell ya what the latency on my FS system is. I run TQi and DX3's back to back with the FS and haven't noticed. Maybe it's not so bad, IDK.
As to the saver spring, even tightening the stocker too much had me breaking steer links and stripping servo gears, so I backed it off till I stopped breaking things. A racer I'm not, just a wanna be, LOL

 

[Shakka Lakka]

I'm quite old, but my reflexes are still decent.

Latency is 100% a thing that you would definitely notice if you were doing a side by side comparison. Even if you're old.

I fly FPV drones. You really want the lowest latency possible, especially if you're flying through gaps etc. Typically my goggles operate with a latency of 28ms. The plus side, I get to see a HD picture with no noise. This seems an acceptable compromise.

With RC cars, if you drive a touring car around a track with a poor radio and slow steering servo - you'll 100% see the difference. The thing is - you still have to put in the right input - lower latency, HRS, FASST etc - it doesn't drive for you. But it will work for you if you're putting in the right inputs. Below 15ms, latency has no impact on human performance.

My FASST 3VCS operates at 11ms latency, which even after 20+ years is still pretty much as good as it gets. Which is why I don't change my radio. That and the fact that they don't make stick radios like that any more.

There's no disadvantages of having a responsive radio. Or one that offers full range - that's really important for bashers that drive in very wide open spaces, or speed runners that run their rigs over 1/4 mile away.

My BEC voltage is often limited by my choice of receivers, but that's because I'm a big fan of Futaba FASST Receivers. They're as rare as Unicorn tears and expensive, so I won't risk magic smoke by using 7.4v instead of 6v.

And for the majority of us - why risk it? More speed and power - but via a high latency, RTR radio? Pointless as tits on a bull!

My choice of Protek and AGF servos work well on 6v. I select the specs based on their 6v performance, generally. Except my Savox on the Baja, which is a comparatively slow servo @0.21s/60° and 30kg of torque at 6 volts, but I still have no intention of running higher voltage because of the Futaba receiver.

Where I use FRSky FASST Receivers, they allow voltages up to 10v, so I could put the Torox 185 to 7.4. - but I generally don't. I conserve the energy for propulsion.

The other thing to consider is the servo saver spring on Corally rigs. If it hasn't been upgraded to a higher rate spring, none of the extra torque & speed from the extra 1.4v is ever going to reach the wheels.

This is actually really interesting information, thanks for the detail. I did wonder if thrust power is reduced a little when upping the voltage to the servos, also if you run fans off the receiver then when you increase the BEC voltage I guess the fans start to take the higher voltage too? Do you by chance have links for the upgraded servo spring required? Thanks.

 

[Horatio]

I couldn't tell ya what the latency on my FS system is. I run TQi and DX3's back to back with the FS and haven't noticed. Maybe it's not so bad, IDK.
As to the saver spring, even tightening the stocker too much had me breaking steer links and stripping servo gears, so I backed it off till I stopped breaking things. A racer I'm not, just a wanna be, LOL

Experienced drivers will drive around any short comings in latency. Even though it's noticeable over 25ms, studies show that human performance isn't significantly impacted, even with latency up to 50ms - provided the latency doesn't vary constantly by a significant amount. In that regard, signal stability is more important than the lowest latency technology can achieve.

The combination of higher response servos, with faster transit time, all increase that 'connected' feel. I remember being handed our 'fast' guy's radio and driving his car. His steering servo was 0.08s/60°. Mine was 0.13s/60°. The immediate consequence after getting into the groove with my own car was that I was turning in too soon with the faster servo and launching off dots.

It took a dozen or so laps for the old brain calibration to kick in (memory muscle). Conversely, when he took to the track with my car, he was turning in too late. Accordingly, it took him a dozen or so laps to get the lines right.

The thing with tightening the stock spring, is that the gap between the coils becomes so small, you end up with no give in the system to save your servo in the event of a tumble or impact. I think the probability of a spike or the servo being over loaded, blowing the IC, increases with higher voltage being run. Combine that with people not using the mounting grommets + a RTR servo = magic smoke.

 

[Shakka Lakka]

Experienced drivers will drive around any short comings in latency. Even though it's noticeable over 25ms, studies show that human performance isn't significantly impacted, even with latency up to 50ms - provided the latency doesn't vary constantly by a significant amount. In that regard, signal stability is more important than the lowest latency technology can achieve.

The combination of higher response servos, with faster transit time, all increase that 'connected' feel. I remember being handed our 'fast' guy's radio and driving his car. His steering servo was 0.08s/60°. Mine was 0.13s/60°. The immediate consequence after getting into the groove with my own car was that I was turning in too soon with the faster servo and launching off dots.

It took a dozen or so laps for the old brain calibration to kick in (memory muscle). Conversely, when he took to the track with my car, he was turning in too late. Accordingly, it took him a dozen or so laps to get the lines right.

The thing with tightening the stock spring, is that the gap between the coils becomes so small, you end up with no give in the system to save your servo in the event of a tumble or impact. I think the probability of a spike or the servo being over loaded, blowing the IC, increases with higher voltage being run. Combine that with people not using the mounting grommets + a RTR servo = magic smoke.

I've heard a lot about this magic smoke...I think I'll stick to 6V lol

 

[Horatio]

This is actually really interesting information, thanks for the detail. I did wonder if thrust power is reduced a little when upping the voltage to the servos, also if you run fans off the receiver then when you increase the BEC voltage I guess the fans start to take the higher voltage too? Do you by chance have links for the upgraded servo spring required? Thanks.

Yep. If you increase the voltage, everything gets it.

The Upgraded spring is from LeeSpring.

LC 085J 0 M

This is the number of the spring which was carefully measured for size and rate. It's slightly taller and has more more space between the coils, with thicker music wire (the best metallurgy for springs).

The downside is that the manufacturer only accepts orders to the value of £30, otherwise they charge an admin fee of £20.

So as a minimum, you really need to order 10 springs and sell the surplus ones.

So, instead of this:

You have this:

The stock spring I can readily compress between my finger and thumb.

But it ain't happening with the new spring. Even if you're juiced up!

 

[Shakka Lakka]

Yep. If you increase the voltage, everything gets it.

The Upgraded spring is from LeeSpring.

LC 085J 0 M

This is the number of the spring which was carefully measured for size and rate. It's slightly taller and has more more space between the coils, with thicker music wire (the best metallurgy for springs).

The downside is that the manufacturer only accepts orders to the value of £30, otherwise they charge an admin fee of £20.

So as a minimum, you really need to order 10 springs and sell the surplus ones.

View attachment 6692

So, instead of this:
View attachment 6693
You have this:
View attachment 6694
View attachment 6695
The stock spring I can readily compress between my finger and thumb.

View attachment 6696
But it ain't happening with the new spring. Even if you're juiced up!

legend! thanks for this, at least I got replacement spring sizes sorted

 

[KnowAir]

legend! thanks for this, at least I got replacement spring sizes sorted

@Horatio is a wealth of knowledge! Not a bad fella either! Thanks Horatio!! Much respect Sir.

 

[Horatio]

My thank you, kind sir!

All the forum members contribute loads of helpful stuff here - not just about Corally rigs - there's a broad range of knowledge.

I enjoy the conversation when I can.

I'm gigging tonight - Rock & Soul - and both our Saxophonists are playing, which is great!

I'm really looking forward to it.....

 

[KnowAir]

My thank you, kind sir!

All the forum members contribute loads of helpful stuff here - not just about Corally rigs - there's a broad range of knowledge.

I enjoy the conversation when I can.

I'm gigging tonight - Rock & Soul - and both our Saxophonists are playing, which is great!

I'm really looking forward to it.....

Break a leg brother!

 

[Horatio]

Break a leg brother!

Cheers dude!

 

[Shakka Lakka]

My thank you, kind sir!

All the forum members contribute loads of helpful stuff here - not just about Corally rigs - there's a broad range of knowledge.

I enjoy the conversation when I can.

I'm gigging tonight - Rock & Soul - and both our Saxophonists are playing, which is great!

I'm really looking forward to it.....

Oh that sounds so cool! Hope it goes well man

 

[Horatio]

Oh that sounds so cool! Hope it goes well man

Cheers bud. It's a nice venue next to the Sea, so hopefully everyone is up for it.

Old school!