"Set frame rate limit" causes intermittent stuttering

Hey guys. I need to limit my frame rate to 60fps however I haven’t been able to find a way to do it without a really annoying stutter problem.

My game runs at 160fps with the limit turned off and is very smooth. However setting the limit at 60fps causes slight stuttering every 5-10 seconds which feels like the frame rate is dropping, but it’s not. In between the stutters it’s very smooth. I’ve already googled and found a couple of people that had the same problem and I’ve tried the ‘smooth frame rate’ option but nothing seems to make any difference. Anyone got any ideas? Cheers!