Shimano 9sp cassette - loose top three

[HF2300]

Shimano HG50 9 speed cassette - looking at the Shimano diagrams I think the bottom 6 sprockets are assembled as a block, while the top three (smallest) are separately fitted, is that right?

Anyway, the smallest three on this bike are loose and can be moved easily on the lash on the splines. Is that correct, or does it imply that the locknut is loose?

 

[jpembroke]

Yes, probably a loose lockring although I have seen this problem on some wheels (Mavic) where a small spacer that should sit behind the cassette has not been fitted (got thrown out with the box).

Anyway, most likely a loose lockring.