What size Hex wrench is needed to install the P1 or Single-Sided Pedals? January 07, 2022 21:53 Updated Installation of the P1 or Single-Sided cycling power metes require an 8mm hex wrench. Related articles Do I have to set my crank arm length on the P1 or Single-Sided Pedals? What type of cleats do the power pedals use? Are the P1 pedals compatible with Garmin's cycling dynamics? Comments 0 comments Article is closed for comments.