An aerosol can of motorcycle chain oil sprayed onto the edges of the leaves will penetrate most effectively. Get the one that is suitable for o-ring chains so as not to damage any rubber bushes.
I do mine just once a year.

Doug
2011 Plus 4 in Rich Maroon

1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900