Intake camshaft isn't rolling over smoothly

Bike seems to run ok but when I'd heard something odd, I shut it down and rolled it over with 17mm wrench. I pulled valve cover off and then watched as I rolled it over, the intake cam was sort of jumping/snapping forward. I'm afraid it'll jump teeth on cam gears . Why does this happen? Sorry bout my description, it's not easy to describe what's happening. Thanks!!!

Little background required. Is this a result of recent work or has this suddenly started happening without you having touched anything?
Possible causes if its been worked on. Cam caps put back in the wrong positions, back to front or over tightened. Cam chain incorrectly tensioned or adjusting the cam chain has exposed a badly worn or damaged cam chain.

If its developed on its own its likely cam chain needs tensioning correctly.

Wow! It was happening because I'd slightly over tightened. I don't use a torque wrench for these (I don't have right one), ..knowing that 12 in lbs is really not much at all, rather I use a small, short handled ratchet. All is good now. Thanks Warren3200gt!!