RC OMG LP-CM07S SERVO OVERHEATING

My RC OMG lp-cm07s servo mounted in my d4 seames to be running hot as after about  5 minutes of run time the servo becomes to hot to touch. I have no way of accurately mesuring the temperature. Is this ok or do i need to change the esc(SP reventon R) settings or even put a fan on it.

Thanks in advance
Franek