Recently installed a new fsa os99 carbon stem, and tightened it up to the torque recommendations. Everything seems solid enough, except that when I hold my tire straight and give the bars a good jerk in either direction, I can get the stem to slip. I do have to give it a pretty solid jerk, but should I be able to do this? I have ridden it a couple times since, and have not had any slippage during my rides at all. I was however a little nervous on my latest descent. Just curious what you guys thought.

Thanks!