I recently completed the rebuild on my CB750 k2 engine. I used the CycleExchange method (drill oil pump) to prime the oil pump. Good pressure and oil to the head etc. I then attempted to crank the engine with the battery from my BMW motorcycle (relatively new battery that started the BMW today). Engine cranks very, very slowly, then stops. I checked and the cleaned starer per the Hackaweek episode. Would it acceptable to use a car battery to get this to crank and check oil pressure when cranking (just want to ensure no issue before I take the steps on dropping this in the frame)? Am I missing something? When I watch the videos of other doing same test engine cranks away. Thanks in advance for your assistance.