almost broke my wrist.......

I recently put a new cam and 1.3 ratio rockers on my predator 212cc motor. The compression release works and the valves are adjusted right. It starts after two or three pulls, but sometimes it yanks the cord out of my hand so hard its kinda scary.
The comp release is not working right if it does that , probably the valves are not set right . Set them to zero and be a little past top dead center .