Went to change the sprocket today and noticed the old one was a little loose, as in it could wiggle around on the shaft even with the sprocket bolt tightened on. I checked with the new sprocket and it has some wiggle room too. I thought maybe the washer on the sprocket bolt is supposed to be a dome washer to hold the sprocket in place, so I checked my factory service manual and says nothing about it being a dome washer or a wear item to be replaced when changing sprockets.
The splines on the shaft don't look worn and the sprocket is for sure not worn because it's brand new. I checked a parts diagram and it shows no spacer is supposed to go anywhere around there so I don't think I'm missing parts.

So does anyone know why my sprockets might be wiggling around on the shaft?

In case it's relevant, it had a 520 chain and sprockets from one of the previous owners. I'm going back up to the original 525 size chain and sprockets.

 

A little bit of play is normal for the front sprocket.

So long as the sprocket bolt is tightened to the correct torque there's nothing to worry about

 

Dont bother with the 525, stay with the 520.

 

The front does float around a bit.

I spearrd a dab of silicone around the edge of the washer and let it dry. The sprocket still floats, but it isn't quite as noisy.

 

Good to know. This really surprises me. I've never had a bike that just lets it float around like that before. I have another bike with a similar countershaft bolt but it has a dome-shaped spring washer to hold it still.