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  1. #1
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    Should I get external BEC for erevo 2.0 after changing servo with 7.4v ?

    I just upgraded my erevo 2.0 servo to dual savox SB2290SG thats able to run 7.4v.
    My question is, should I get external BEC Castle 10 AMP Peak 6s (25 max in) 4.8-9v out ? I run with 6s lipo.
    Will the stock ESC provide enough power?

    I prefer not to get external BEC if possible to avoide complicated setup.
    What the advantages do I get if I decided to get external BEC?
    What I missed out if I do not get external BEC?

    Thank you.

  2. #2
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    Oh mama, you got 68lb of torque with a pair of these at 6v.

    At 7.4v, it will steer a tad faster, and that's what I'd go with.

    Looking at YouTube videos, amp testing is about 5A max. I highly doubt your ESC built-in BEC can deliver this much, so I'm pretty sure you will have to get an external BEC.

    Sent from my VTR-L09 using Tapatalk

  3. #3
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    Quote Originally Posted by baibaiman View Post
    I just upgraded my erevo 2.0 servo to dual savox SB2290SG thats able to run 7.4v.
    My question is, should I get external BEC Castle 10 AMP Peak 6s (25 max in) 4.8-9v out ? I run with 6s lipo.
    Will the stock ESC provide enough power?

    I prefer not to get external BEC if possible to avoide complicated setup.
    What the advantages do I get if I decided to get external BEC?
    What I missed out if I do not get external BEC?

    Thank you.
    Ok so even if your esc bec could handle the 7.4v I highly recommend not putting more then 6v through the reciever. I know a lot of people on here have and don't run into problems but a reciever costs more then a bec and running the rx bypass harness your guaranteed your max servo voltage.
    Bec's are basic to instal and well worth the time it takes and solves any glitching issues you might have with high voltage servos.
    https://forums.traxxas.com/showthrea...rvos-and-tires

  4. #4
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    Quote Originally Posted by Rain Dawg View Post
    Ok so even if your esc bec could handle the 7.4v I highly recommend not putting more then 6v through the reciever. I know a lot of people on here have and don't run into problems but a reciever costs more then a bec and running the rx bypass harness your guaranteed your max servo voltage.
    Bec's are basic to instal and well worth the time it takes and solves any glitching issues you might have with high voltage servos.
    https://forums.traxxas.com/showthrea...rvos-and-tires
    Sorry english is not my 1st language. So basicly you recommend to have external BEC?

    Thanks

  5. #5
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    If you want to run 2 servos at anything above 6v I would recommend running an external bec with the bypass adapter and leave the esc bec to power everything else.
    It works really well with no issues and it's a minimal cost for peace of mind.

  6. #6
    RC Champion nickruger's Avatar
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    I second running the bypass for the reciever, I know lots of people have run the traxxas reciever at higher voltage without issue, unfortunately I have not. I ran the traxxas reciever at 7.4v for a few weeks and eventually killed it.

    Sent from my SM-G920V using Tapatalk

  7. #7
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    Yup I agree with all others. Add an external bec. I run dual savox servos in my Summit. Works awesome. Would recommend one to anybody thinking of running an HV servo such as yours. Great investment as will be a castle link to adjust the voltage of the external bec.

  8. #8
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    Are you using Dual SB2290SG?

    Quote Originally Posted by baibaiman View Post
    I just upgraded my erevo 2.0 servo to dual savox SB2290SG thats able to run 7.4v.
    My question is, should I get external BEC Castle 10 AMP Peak 6s (25 max in) 4.8-9v out ? I run with 6s lipo.
    Will the stock ESC provide enough power?

    I prefer not to get external BEC if possible to avoide complicated setup.
    What the advantages do I get if I decided to get external BEC?
    What I missed out if I do not get external BEC?

    Thank you.
    Am I wrong or does two 7.4v pushing over 600 pounds of torque seem like a lot .

  9. #9
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    Nope not all all. Having torque, and itís not pounds but ounces of torque is not a bad thing. You will need to get an external bec to get the most out of those servos. And by doing so youíll relieve a lot of strain on the internal bec of the ESC. The CC bec is a great addition to any rc vehicle as it does allow for a more tailored setup being you can adjust voltage to your liking. By tapping into the main lines of the ESC battery plug you can safely run 6s and control the voltage through the CC bec. Youíll need a castle link or field program card to do so. But once set you can enjoy the full potential of your servos. Hope this helps and good day.

  10. #10
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    In my experience using the stock esc shouldn’t need any external BEC, except if you want higher voltage like this guy wants. For the OP, yes it would be better for you. But for someone using less power hungry stuff it’s not necessary. Even this mxl 6s pushes 2 savox servos 2 fans and 1 big computer fan around with no heat issues in the summer. However, that was because I only needed 6 volts.

  11. #11
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    The newer ESCís have a much better bec in them. I know the older ESCís donít have the amperage to push a bunch of stuff like fans and such. Makes a lot of heat. Adding an external bec isnít a bad thing and does allow for high voltage servos to be used such as the OP has.

  12. #12
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    Thank you!

  13. #13
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    So if you run two Savox 6v servos like Savox SA-1231SG, you don’t need the BEC.....?

  14. #14
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    Yes and no. IMO, having an external bec helps the ESC. Keeps it from stressing. But like said these newer ESCís have a much better internal bec. Read up on external becís and then you can make your own decision as to whether you want to add one.

  15. #15
    RC Champion nickruger's Avatar
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    Quote Originally Posted by REVO-KN-EVIL View Post
    So if you run two Savox 6v servos like Savox SA-1231SG, you donít need the BEC.....?
    I'm not trying to sway you, but I run a single 1231 with no external bec and 444oz is plenty for me. The amount of torque you would get with 2 is in my opinion completely not necessary. Like I said you might want that much, if you do you could try them without one, you'll know pretty quickly if you need to add an external BEC. If you go with a single 1231 you should be good. Mine was fine with the vxl6s and the current mamba monster x I have in there.

    Sent from my SM-N960U using Tapatalk

  16. #16
    RC Champion FnFancy's Avatar
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    Quote Originally Posted by nickruger View Post
    I'm not trying to sway you, but I run a single 1231 with no external bec and 444oz is plenty for me. The amount of torque you would get with 2 is in my opinion completely not necessary. Like I said you might want that much, if you do you could try them without one, you'll know pretty quickly if you need to add an external BEC. If you go with a single 1231 you should be good. Mine was fine with the vxl6s and the current mamba monster x I have in there.

    Sent from my SM-N960U using Tapatalk
    And a second to this, the 1231 is all you need. Why deal with the hassle of keeping two servos synced up when the 1231 will do the job without a bec. Maybe I am trying to sway you but, it truly is the way to go.

    Sent from my SM-N960U using Tapatalk
    Its alright son I'll fix it when you break it

  17. #17
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    Didnít know that servo had so much torque. I have to agree, donít see the need for 888oz of torque! Youíll be just fine with one servo and no bec as said! 444oz of torque is plenty to turn the wheels without question. Try one servo and youíll see it will be plenty.

  18. #18
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    Dual 1230sg's .... no bec

    https://www.youtube.com/watch?v=Jf3ue2zmduo

    Might have to take one out... to even things out
    E-Revo VXL 2.0
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  19. #19
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    Yep. With both I would recommend getting an external bec for sure. Are they turning by themselves? If so they may be hungry for power. Try unplugging one and see if it still does it.

  20. #20
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    With one is fine

  21. #21
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    Then heís for sure you need an external BEC. I know the CC BEC will work well for that setup as I am running 2 savox servos in my Summit. The arenít the same as yours but they are HV servos made to run at 7.4vdc. With the bec I am able to run both of them with no issues and have been for well over 5yrs now. Those savox servos are amp hungry for sure and that is what is most likely the cause of the issue you are having. Just not enough amps to keep up with both of them.

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