From memory the absolute torque loadings peak at around 1150 lb/ft. Quite scary!
1150?! How can that be?
Extremely short spikes of torque. The normally quoted torque figure can be thought of as an average over a couple of revolutions of the crank. The inertia of the mass of the crank will help smooth things out compared to a lightweight crank but the S&S needs more help than most.