elling_j

I was wanting to know if my sons car should be making a high pitch hum as soon as we turn the car on. We are new to this and any help is great.

Thanks

St33v3

My Feedback: (1)

It might be the steering servo.

Try turning the wheels to see if it stops.

NewRageRC

My Feedback: (1)

A whining sound is pretty typical of AM radios.

im_a_rcav8r

I am in the process of writing a review of the Sumo R/C line of 1/24 scale vehicles.  I have 3 of them that I have been testing for about 40 days now (with the help of my 7 year old son).  Without intentionally breaking the trucks, I am attempting to tear them up with hard core use including large jumps landing on cement, running 7.4 volt lipo batteries and running in dusty/dirty conditions.  

Now that my preamble is out of the way – all three of my trucks make the sound you are describing.  I have not investigated the origin, but I will.  I am not sure if it is from the speed control, motor or steering servo.  My guess is that it is coming from the steering servo.  I have had other servos make the same sound on trucks, helicopters and planes and it is quite normal.

Have fun with your Sumo – and you may want to look into some of the upgrades like the faster motor – with good batteries and the motor upgrade you can do wheelies.