In Ohio the best roads are generally south and east of I-71, and there are many fun roads. Any route that goes uphill away from the Ohio River toward the interior of the state is a good bet, especially the triple digit roads like 763, 775, 555, 260, etc... Two digit roads like 41, 78, etc are usually less twisty but still very good. Clusters of great riding can be found around Hocking Hills State Park near Logan or in Amish country near Dover, but perhaps the best is around Marietta in the southeast. I'd be glad to help you narrow it down a bit when your plans are taking shape. Are there any kinds of sights you want to see along the way?