Is the stock shock for a 2007 Roadking Classic 12" or 13" ?
The drag specalties fat book cross reference in the back of the book&nbsp\\;says 12" but mine measure 13"

 

Your Roadking is 13" . You can confirm this by pulling off your bag and measure bolt to bolt once your rear wheel is jacked off the ground. If you are buying shocks consider a YSS for an inexpensive shock $165 (chrome pair) or $585 for Gas. Penskes are $997/pair but worth every dime if you want the best.