S1s have a single circuit. Bleeding is ridiculously easy. First bleed the master by making a short outlet line that goes into the reservoir. It can even be rubber hose. Hook up the brake line. Go to farthest bleed nipple. Put a length of hose on it that flows into a container. Open the bleeder. Pump the brakes 10 times. Close the bleeder. Refill the brake fluid reservoir. Repeat for the next closet, etc, until you have done them all. Repeat but just do 3 pumps this time. You brakes are bled.