Originally Posted by gti5notrkt
The Spectrum H5020G specs show it to be wicked fast at 0.05s/6v however when I looked at a setup sheet from the Viper ESC website it showed the servo BEC set at only 5v (the VTX1 goes up to 5.5v). So my question is, why would you not want the servo to be as fast as possible? Is there a situation where a steering servo can be too fast?
Also the H5020G is rated at email@example.com and 39oz/in@6v. Is this enough torque?
BEC/Boosters that are built into a speedo have to be as small as possible. The higher the voltage and amp output the bigger the booster has to be to be reliable. 5-5.5v boosters that supply 1-2A are easier to package inside a speedo.
For pan car applications there is no such thing as a servo that is too fast. Servo speed lets you make corrections mid corner that you could not achieve with a slow servo.
If you are jittery or your car is unstable you can add 10-15% negative exponential to your radio to make your steering feel smoother right off center. Most mid to top grade radios will allow you slow a servo down but for 1/12th or WGT this is not a good idea and usually is done to cover up a driver or setup problem. Its better to address the root cause, a driver with the shakes, or a poor setup that is excessively responsive off center (too stiff side springs, too heavy side damping, etc).
The H5020G had more than enough torque. A Kimborough servo saver will deflect at way less than 30 in/oz of torque. I can grab my wheels and force them left and right deflecting the servo saver and my 5020 doesn't budge.
There are cases when a servo could be too fast like rubber tire sedan and off road racing. A servo that is too fast can move a rubber tire too fast for it to maintain traction. Servos much faster than .09 sec are not useful in these applications. Our foam tires do not have these issues and faster servos generally enhance our levels of control.
This is a new ground as only in the last year or so have mini servos been available to us capable of these speeds. Many of the racers here are just sticking with what they know Futaba 9650, Spektrum 5010, Airtroincs 94761, etc. However, we have better alternatives now.
Also, when it come to toughness the H5020G is a Heli Tail Rotor servo meant to be driven by a Digital Gyro. It is designed to center and actuate more precisely, deal with more inputs per second and dissipate heat levels far beyond anything it will experience in a R/C car.