If you stood each wheel on 4 scales (assuming the weight distribution is 50/50) you would see a reading of 125g on each scale.... but that would be a total of 16 scales which would be expensive
I know what you mean though. if each wheel sat on 1 scale you would expect to see 500g on each assuming that the chassis is level. If the chassis wasn't level or distribution isn't 50/50 you should still be able to add the 4 figures up to make a total of 2000g.