Have you lost your frame plug on your Suzuki DR650? Or maybe a passenger accidentally kicked it off with their boot?
 
Whatever the reason, those frame plugs help keep the water and grit away from the swingarm axle.
 
Make sure you choose the correct side (Right or Left). This one is the Right, with a larger diameter covering the axle nut side.
 
This is a Suzuki Genuine Parts:
43585-32E00-000 PLUG,FRAME PIVOR,R