Washers on Sprockets

[JesseK]

Spin the wheel without chain attached to it. If the sprocket doesn't wobble, you're fine. in other words, if the sprocket is perfectly parallel to the wheel, you're fine.

If it does wobble, then consider shaved off washers as shims, or use spacers as suggested above.

[MrForbes]

Looking at the pictures, it looks like they might be springs, not washers....