I found one solution, which helped me!
So you need to Lerp weight, and on early moments VR IK will setting up on small coefficent of weight, and this will be unnoticed !
Here is coroutine example:
private IEnumerator FadeOut(float start, float finish, float time)
//yield return null;
float elapsedTime = 0;
ikManager.solver.IKPositionWeight = start;
while (elapsedTime < time)
ikManager.solver.IKPositionWeight = Mathf.Lerp(start, finish, (elapsedTime / time));
elapsedTime += Time.deltaTime;
yield return new WaitForEndOfFrame();