Built a conversion from an old KHS road frame and parts from my LBS about a month ago. Ive been getting what seems to be some left-right movement in my right crank. I find that after I ride I need to re-tighten the crank bolts, almost a full rotation.
Origin-8 crank and chainring
salvaged the old pedals
KMC chain
Sugino BB

It only happens at the top of the rotation (when my right foot is nearest to the top tube)
Any help would be greatly appreciated