Hello, I just returned from 7 day trip to Texas hill country. 7 buddies with me, we rented bikes from Cowboy Harley in Austin. Very good operation to deal with. I am not sure of any other options in that area to rent bikes from. Check Hillcountrycruising .com they might have a list of rental companys.
We did 1200 miles in 7 days. We stayed in different towns every night, Kerrville, Bandera, San Antonio, Port Aransas, New Braunfells, and Fredricksburg.
I must say that we enjoyed every minute of trip. Beautiful roads and wonderful people in that area.