Hi Homer,
can you please be a bit more precise: "Starter is not engaging, all the cogs are turning" - which cogs are you talking about? Those inside the starter, i.e the planetary drive? Or are you talking about those behind lhs engine cover?
Most frequent issues with starter are these:
1) outer ring of planetary drive (inside starter motor) is slipping. It should be fixed to starter housing, but in some cases it slips. It can be fixed again by adding thin washers between outer ring of planetary drive and starter housing, or just glue it together, 2 component glue did work on my bike.
2) starter clutch (behind lhs engine cover) slips - starter clutch should be replaced - or just welded together, outer housing and inner ring - works fine since about 10 years on my bike.
First thing you should do is to open the lhs engine cover, to review whether there is a mechanical issue with the starter gearings or with the starter clutch. Cover needs to be opened anyway, regardless whether any mechanics inside starter or in the engine cover are affected.

Jürgen