You are right,Brian. But he said it is a new engine so I'm try to explain how and why. That is why I asked him to check the crank size of his two cranks.
Most engine manufactory produce all parts except bearings.(of course I knew some manufactories produce bearings self) Most of them just buy bearings from big bearing manufactories or bearing suppliers. Engine manufactories can control all the sizes except bearings. Sometime it is hard to control the bearing size. Maybe this batch it comes with 7.00mm inner ring,but next batch is 7.02mm inner ring. If your crank is 6.98mm designed for 7.00mm inner bearing ring,but you got a bearing which has 7.02mm inner ring? With a 0.04mm tolerance you will feel it loosely. But if the tolerance is too small,it is hard to assemble.