Phil...I e-mailed Jeff the same question when I got my Raven One last year. His response:
Standard oiling is one drop on the ball of the spindle bearing and one drop in the bearing well. If two drops, ok but, no more.
I would do it every 6 months. Each time, wipe each surface clean with a dry cotton cloth. No chemicals and then, re oil.
Best wishes,
Jeff
Though I feel Thomas' recommendation sounds more correct, Elinor's comment on use makes good sense.