Servo for TRX-4

[RCTom]

I need to replace the stock servo in my TRX Bronco after it failed. There are already lots of posts about swapping servos and after reading them I've narrowed it down to a few options. But I still have questions that weren't answered in the other treads.

I like the Holmes SHV500V2 due to being able to plug the servo into the AUX plug at the ESC (I still have the stock XL5). But my question is how do I plug in the light kit I have that uses the same plug? Will a Holmes RX bypass adapter allow me to use both? Then what happens if I swap to a Hobbywing WP 1080 ESC (which I may also do at some point)--how do I hook up the SHV500V2 and light kit?

I also read great things about the Hitec 7950 and Savox 1230SG servos. It's my understanding that finding a 24 tooth servo horn for the Hitec that fits a TRX-4 is a problem--is that still true or what arm would I buy?

As for the Savox, I've read that it's very powerful but also quite noisy so I'm not sure about this one. I'd really like to keep my rig as quiet as possible. Above all else though, whatever solution I go with I don't want to use a BEC.

Last, what other parts would I need to get this project done--like a servo arm, servo wire extension, or even a servo mount (Bowhouse RC or Yeah Racing come to mind)?

What do you guys think?

Thanks!

[svt923]

Originally Posted by RCTom

I like the Holmes SHV500V2 due to being able to plug the servo into the AUX plug at the ESC (I still have the stock XL5). But my question is how do I plug in the light kit I have that uses the same plug?

Plug in a JST Y connector and you can plug both of them in. Just make sure to get the correct orientation because you can buy the Y connector reversed from what is needed.

Originally Posted by RCTom

Then what happens if I swap to a Hobbywing WP 1080 ESC (which I may also do at some point)--how do I hook up the SHV500V2 and light kit?

You solder a JST pigtail onto the battery leads of the 1080. It is easy enough for even basic soldering skills.

[RCTom]

[QUOTE=svt923;5898466]Plug in a JST Y connector and you can plug both of them in. Just make sure to get the correct orientation because you can buy the Y connector reversed from what is needed.



Thanks for the info! Just to verify--this is the correct orientation I need with two male and one female connector, right?

Also, if I decided to go with another brand servo (like the Hitec or Savox), would the wiring be the same?

[Inspector86]

The red JST connector on the stock XL5 ESC is simply a tap off of battery voltage. Using a Y cable like the one above is a good way to add an additional JST male power source or HeyOK sells a JST power block with up to 5 male connectors or you can solder in a JST plug to the battery connector. Also, keep in mind that the stock TRX4 electronics are all rated at 6v so if you install a servo which requires a higher voltage you will need to provide that higher power from some source either direct battery connection or a BEC. This is one reason why I recommend the Savox 1230SG or 1231SG because it they are rated at 6v which makes them nicely compatible with the stock electronics. The 1230/31SG noise issue is true but it is not nearly as loud as some would have you believe and even then it only occurs when the steering is in a bind. To install the 1230/31SG you will need a 6" servo cable extension and a metal 25t servo horn like the Traxxas 8247X.

[RCTom]

So it sounds like a BEC is NOT required with a 1230SG since it makes that much power at 6.0V. So is the reason for brownouts with other servos is that they operate at greater than 6V?

How many amps does one of these popular high torque servos draw during operation?

[AnimalHippie]

Get a hobby wing 1080esc it's a great budget ESC. If you're on a tight budget there's two great servos that come to mind. Power HD 20k and turnigy 959v2. Neither of them need anything special to run. If you're not worried about budget or have a higher one then me promodeler 470 or 630 is the way to go in my mind. They like to be ran off straight 2s power. Personally I don't like savox servos. Never owned one but have ran next to guys with them. They are noisy and I've seen allot of bad from them in my research. Good luck!

[RCTom]

Thanks for the help guys. For now, I'm going the Holmes SHV500V2 and JST Y connector route to get my Bronco running again with the least amount hassle (for my skillset, anyway).

However, since I was already ordering from RPP, I went ahead and added a couple of HW WP 1080 ESCs, Traxxas 8247X servo arms, and six inch servo harnesses to my order to for the eventual steering servo replacement in my Defender.

This way I figure I can do my own Holmes vs. Savox servo showdown sometime in the future.

BTW, I didn't order the Savox 1230SG yet because my LHS always has them in stock so I know one will be waiting for me there when I need it. That way I can throw a little business there way too.

[Inspector86]

Originally Posted by RCTom

So it sounds like a BEC is NOT required with a 1230SG since it makes that much power at 6.0V. So is the reason for brownouts with other servos is that they operate at greater than 6V?

How many amps does one of these popular high torque servos draw during operation?

Depends on the ESC. The stock TRX4 XL5 ESC will required a BEC, even Traxxas knows this which is why they relesed their own BEC as a fix. The HW1080 will normally work just fine without a BEC but many add one anyway.

[xlostonex]

I like the reef444. They are really good servos. Super durable and very quiet.

[RCTom]

Originally Posted by Inspector86

Depends on the ESC. The stock TRX4 XL5 ESC will required a BEC, even Traxxas knows this which is why they relesed their own BEC as a fix. The HW1080 will normally work just fine without a BEC but many add one anyway.

Inpsector, I believe I read on a previous servo post I searched up that you were running a 1230SG servo with a stock Traxxas ESC on one of your TRX's and you said it was working OK. Did you also have a BEC installed?

[Inspector86]

Originally Posted by RCTom

Inpsector, I believe I read on a previous servo post I searched up that you were running a 1230SG servo with a stock Traxxas ESC on one of your TRX's and you said it was working OK. Did you also have a BEC installed?

Back in July/Aug 2017 when my #1 TRX4 was still mostly stock I had to replace the stock servo and installed the 1230SG. I ran the 1230SG with the XL5 for a week or so with no BEC until I could install the Mamba-X but as I recall the XL5 ran warm during that time.