Just a thought - I 'revived' my rollerhead bearings, which were also quite 'ratchety' (from a 30-year rest) without removing them. I applied a puddle of light machine oil onto the top surfaces and spun them a bit to distribute oil downward. Worked well. A few more 'soakings' and they turn effortlessly. A good cleaning of the bearing outer surfaces with a brass brush to shiny new looking, along with using some WD-40 to clean up and dry down the arm roller races, followed and my motor/yoke assembly floats effortlessly in the arm now. Also added some oil over the top of the king pin and it seeped in enough to add some silkiness to its movement too.