Good? Whatever suits you at the moment based on conditions, including terrain.

Crossing the country in 93 days with a group, we generally rode 5-6 days and then took a day off. We probably averaged about 60/day on the days we rode. During two solo, 7-8 week tours the following year, I didn't stick to a rigid schedule. Several short days when the mood hit me and several multiple days off in a row when I found places I liked.