The start of ZZ Top‘s summer tour has been pushed back for bassist Dusty Hill to undergo surgery this week to remove two kidney stones.

The stones were discovered in the course of a routine physical examination, but Hill’s doctor advised him that they should be removed immediately so as not to cause any problems down the road — no pun intended.

The affected dates are Morton, Minnesota on July 25th; West Bend, Wisconsin on the 26th; Cincinnati on the 27th; Louisville on the 29th; Asheville, North Carolina on the 30th; and Bethlehem, Pennsylvania on August 1st. The tour will now start on August 6th in Sturgis, South Dakota followed by the start of the ZZ tour with Jeff Beck on August 8th in Missoula, Montana.