Servo Quesions
 

Ok... so I have a 1/8th scale Vorza buggy, and i have recently upgraded my transmitter to an Airtronics MX-3X. I've read a lot of different posts recommending to upgrade the stock servo, but I have a few questions.

The stock servo is a HPI SF-5 SERVO.

• What are the benefits of a servo upgrade?
• What's a decent servo? (Also at a decent price point).
• I've seen people recommend the Hitec 7955tg... what advantages does it offer over the stock?

Thanks in advance!

I am getting a Ko Propo RSx response hc.
I love ko stuff but it is really expensive.

This servo has a metal case so it doesn’t break when under high pressure

the gears are metal so I don’t have to worry about stripping the gears

Its hella fast

Its got enough steering for torque for 8 scale steering

Buying a better servo can give you any of the following depending on which you choose: faster speed, more torque, more durability, better centering, higher resolution (more sensitive to your input), 7.4V voltage capability

These are what I use: http://hobbycity.com/hobbyking/store...idProduct=9983

These servos have amazing speed and torque. The alloy case and titanium gears make it very solid too. Awesome servo for the price.

The main downside is HK being in China means service and support will be very difficult, if available at all. You have to decide if the cheaper price is worth it to you. Buyer beware I guess. Some people don't like HK stuff and that's fine, but personally I have been very satisfied and never had any issues with these servos.

I've used HK for some other stuff before and have not had any issues with the products (though I sometimes prefer to use hobbypartz because of the free shipping if they have a comparable product).

Regarding your comments... how much does torque effect a larger scale model in a servo? Meaning, the higher the torque, I assume the better your turns will be under higher speeds / conditions?

Also, what does it mean to run at 7.4V? How do you do that? I assume that coming directly from a RX it will always be 6V? I guess I'm a little confused there... or does it mean you would have to externally power the the RX with a RX lipo or battery?

Personally I would use the Savox Line of servos.

Try the Savox1256TG. For 80$ its amazing.

Thnaks for the suggestions so far.. that clears up a lot, but I'm still confused about the voltages, and what is required to run at higher voltage (or not?)?...

Ok... so if I understand this correctly, most RX's have a built in BEC that will regulate the voltage to the servo (if you do not plug a RX battery in directly to the RX to bypass the BEC).

I recently got an Airtronics MX-3X system that has a RX that is rated at 4.8-7.4V.

So... my lipo setup comes in well over 7.4V, which means that the RX has as much power as it needs based on the capability of the servo, correct?

Meaning that if I add a servo like the Savox above (which can run at 7.4v), then I can take advantage of the increase speed and torque, correct?

Thanks... just trying to educate myself on this. ;)

What you want to do is run an external BEC that can be adjusted to 7.4V (the Castle BEC is the way to go here!). So you power the external BEC from your main battery, and you don't need any extra RX pack or anything.

Here is a diagram from Castle, I highly recommend their BEC: http://www.castlecreations.com/produ...ec_wiring.html

You can use a lipo RX pack, but to me it makes more sense to use a BEC since you already have a powerful 4-6S voltage source in the main lipo packs. Just need to step the voltage down to a level the servos and RX can use. A lipo RX pack will be larger and weigh more than a BEC, and it's also an extra battery to worry about charging and monitoring, and the voltage won't be constant. Lipo RX pack is only suited for nitro the way I see it.

I use a 7955TG for the mechanical disc brakes on my HARM 1/5 scale and it does a great job of stopping a car that weighs 35 lbs. It's well suited for 1/8 scale steering duty being fast and strong.

Ok... but doesn't the receiver automatically provide that power built in (from its own internal bec)?

EDIT: Ok... I think I was misunderstanding... the BEC output voltage is on the ESC, not the RX, correct? I run a mamba monster, and have the usb connection which (I believe), will let me adjust the BEC output voltage... so, in this case, that is what I would do to enable a higher voltage to the RX (and servo), right?

WOW :nod: That servos specs are sick! I want one! $60 Titanium gear, digital, 400+oz, .16 sec.... I only run electric and power my servos through my reciever. I think they provide like 5v or something like that. Can you run a HV servo withou HV?