It does. As someone else said the air pressure forces the seal onto the shaft hard. However to go and make a claim for any sort of leverage ratio from this wildy mistates the situation.
The seal forces will be completely overdriven by damper/spring effects from the leverage curve. Higher leverage allows the suspension to push through any seal friction at a much higher proportion than the seal friction is increased by running higher pressures.
Notably Rockshox justified the use of larger pistons in the Deluxe/SD lineup in order to allow lower pressures to be run for the same shock force in order to reduce seal friction. This is more of a shock design parameter than a bike design one. Shaft diameter (and therefor seal contact area) also has an influence on seal friction and will offset some of the benefits of larger pistons.
Feb. 29, 2020, 1:31 p.m. - RoboDuck
It does. As someone else said the air pressure forces the seal onto the shaft hard. However to go and make a claim for any sort of leverage ratio from this wildy mistates the situation. The seal forces will be completely overdriven by damper/spring effects from the leverage curve. Higher leverage allows the suspension to push through any seal friction at a much higher proportion than the seal friction is increased by running higher pressures. Notably Rockshox justified the use of larger pistons in the Deluxe/SD lineup in order to allow lower pressures to be run for the same shock force in order to reduce seal friction. This is more of a shock design parameter than a bike design one. Shaft diameter (and therefor seal contact area) also has an influence on seal friction and will offset some of the benefits of larger pistons.