FYI: Familysearch.org is free and has all the Cenuses. Type in the names you're searching for. You can filter by state, county, date, parents, spouses.
If you haven't done this already, I suggest:
** you start with what you know and work backward. Find Sol's descendants in the 1940 Census and trace them back to 1870.
**Check marriage, birth and death records for all of his children.
** And military records -- black men born as early as 1877 are in the draft for World War I, and familysearch.org has the "Old Man's Draft" for World War II, with men as old as 60 registering. His sons may have enlisted in the US Colored Troops for KY during the Civil War.
** If Sol's children survived into the 1900s, study their death certificates (1911 and afterward for KY) for information about Sol (named as father, and where he was born). Familysearch.org may have wills and deeds for Pike Co.
**Check the Catalog on familysearch.org for the Pike County records stored in Salt Lake City. You can order the microfilm of the records at the Family History Center nearest to your home (pay $6.50 first and they will call you when it's available, you go back in and view them).
** Ancestry.com has KY death records from (I believe) the 1850s into the early 1870s. I found my great-great-great grandmother's death record in LaRue Co., KY in 1870. So if you start that 2-week trial with Ancestry, you might try those death records.