Limit Rotation of physics object in 2D

All I’m trying to do is limit a gameobject’s z rotation between two numbers.
I did a whole bunch of research on how to use Mathf.Clamp, and if I understand it correctly, I don’t see why this wouldn’t work:

void FixedUpdate () {
     this.transform.rotation = Quaternion.Euler(transform.eulerAngles.x, transform.eulerAngles.y, Mathf.Clamp(transform.eulerAngles.z, -25.0F, 25.0F));

is there something I’m missing? In the game, the object randomly jolts and twitches and I don’t know why…

The values in transform.eulerAngles appear to be in the range 0 to 360, not -180 to 180. Limiting the rotation to the range -25 to 25 won’t work because of that. Try this instead:

Vector3 euler = transform.eulerAngles;
if (euler.z > 180) euler.z = euler.z - 360;
euler.z = Mathf.Clamp(euler.z, -25, 25);
transform.eulerAngles = euler;

Note also that you are currently not changing the angularVelocity of the rigidbody. For the physics engine it will still appear to rotate, so you might wnat to set that to zero (just for the z-Axis) whenever the rotation hits the limits.