For my Northern rides I use
https://www.por15.com
liberally on all exposed undercarriage components and that stopped rust dead in its tracks.
It can even be applied over existing rusty components but a superior result can be had with their Metal Prep
https://www.por15.com/POR-15-Metal-Prep_p_15.html
This kind of horrific rust doesn't have to happen to our machines.
Mike