Loose Side covers

If the grommets have shrunk but are otherwise in decent condition a piece of heavy duty Shrink-tubing can be placed over the pins as shown to secure the covers.  A mere film of silicone grease aids in the Re & Re but and still allows a secure fit.
 

Good idea!

Sometimes a small detail can ruin our lives.Due to some old and worn rubber grommets I lost a side panel of my Z650 running.Kawasaki grommets, even new, are soft and offer very little resistance as a side panel attachment.I have another BMW brand motorcycle that also has side panels and I decided to use those German grommets to replace the ones on my Kawasaki, the result is much better, the BMW grommets are stronger and more resistant with a thicker profile providing more strength and rigidity to the anchorage of the side covers.Also its price is somewhat lower.I attach photos of the old Kawasaki grommets and the new BMW grommets and their reference in BMW spare parts. Its cost is 11 euros for 6 pieces at any BMW dealer.