Hey super4 bros,s4 newbiehere, recently i heard a knocking sound from my engine, no matter i clutch in or out i still can hear that knocking sound. To explain further, i travel a couple of distance and stop at the traffic light and listen again the sound is still there. Just did my servicing, engine oil and filter changed. Really cant figure out what could have cost it. Need help from experts out there thanx alot.