Laggy changing slider value

Hello guys.I have two scripts.First it is trigger when player get bool isRepair = true.If player exit trigger isRepair = false.In second script i change value slider.
Second script:
void Update(){
if(isRepair){
GeneratorSlider.value += 4 * Time.deltaTime;
photonView.RPC("ActivateGen", RpcTarget.AllBuffered, GeneratorSlider.value);
}
}
[PUNRPC]
void ActivateGen(float s){
GeneratorSlider.value = s;
}
PLEASE HELP ME.WHY SLIDER VALUE SYNC VERY LAGGY