ReStackor User Manual

Finally computer software to tune a shim stack

Mid-Valve Damper Outputs

Each output parameter in the ReStackor-midvalve.xls spreadsheet is defined below. The purpose of the midvalve.xls spreadsheet is to determine the pressure in the compression, rebound and reservoir chambers, the effect of that pressure on release of dissolved gas, cavitation and damping force produced by the shock.

ReStackor_midvalve.xls spreadsheet nomenclature for compression, rebound and reservoir chambers.

Standard Outputs

The ReStackor-midvalve.xls spreadsheet contains separate tabs to compute the damping force of base valves, mid-valve compression and mid-valve rebound strokes. Each tab has an associated output tab describing stack deflection and damping force. Parameters on these output tabs are the standard ReStackor outputs. The parameters are defined in the user manual output section.

The BVc tab of the worksheet contains the standard ReStackor inputs for the base valve configuration. ReStackor calculation outputs are loaded onto the bv_stack and bv_ReStackor tabs of the spreadsheet.

ReStackor-midvalve.xls spreadsheet tab definitions:

Base valve compression or shock high speed compression adjuster calculations
- BVc: Base valve shim stack and valve port geometry inputs
- bv_stack: Base valve stack deflection output table
- bv_ReStackor: ReStackor computed damping force for base valve compression stroke
Mid-valve compression calculations
- MVc: mid-valve compression shim stack and valve port geometry inputs
- mvc_stack: mid-valve compression stack deflection output table
- mvc_ReStackor: ReStackor computed damping force for mid-valve compression stroke
Mid-valve rebound calculations
- MVr: mid-valve rebound shim stack and valve port geometry inputs
- mvr_stack: mid-valve rebound stack deflection output table
- mvr_ReStackor: ReStackor computed damping force for mid-valve rebound stroke

Combined compression damping force of base valve and mid-valve

To combine the damping force of base valves and mid-valves and compute the overall compression damping force follow these three steps:

Go to the BVc tab and update/run the base valve compression calculations.
Go to the MVc tab and update/run the mid-valve compression calculations.
Go to the main Plots tab and hit the "mv_Analysis" and "Load_Output" buttons to compute the combined damping force of the base plus mid-valve.

When the spreadsheet is first opened both the BVc and MVc calculations must be run at least once to write the configuration files to the C:\ReStackor calculation directory. For subsequent runs the BVc or MVc configurations only need to be re-run if the configurations for those valves has been modified.

The Mid-Valve-Calc tab contains the combined compression damping forces for ReStackor base valve and mid-valve calculations.

When you hit the Load_Output button on the main Plots tab of the spreadsheet ReStackor calculations for the combined damping force of the base and mid-valve are loaded into the Mid-Valve-Calc tab of the worksheet. The definition of each parameter on the Mid-Valve-Calc output tab is given below:

U.clk [=] Suspension damper rod velocity with the base valve and mid-valve clickers set at the position requested on the BVc and MVc input sheets.

Pgas [=] Bladder gas pressure or pressure above the ICS piston in the fluid reservoir of the shock or fork, [psia].

Pfrk [=] Pressure in the shock fluid reservoir; [psia]. The parameter name in this column will change from Pfrk to Pics or Pbld (bladder) depending on the configuration of the reservoir pressurization system used in the current calculation.

Pc [=] Fluid pressure in the shock compression chamber, [psia].

Pr [=] Fluid pressure in the rebound chamber, [psia].

Nr [=] Fraction of rebound chamber filled with fluid.

Nics [=] Fraction of ICS stroke or bladder volume used at current suspension stroke.

Fbv.cav [=] Damping force produced by base valve, if the shock is cavitating this force will be different than the non-cavitating damping force computed on the bv_ReStackor tab, [lbf].

Fmv.cav [=] Damping force produced by mid-valve, if the shock is cavitating this force will be different than the non-cavitating damping force computed on the mv_ReStackor tab, [lbf].

Fx.clk [=] Damping force produced at the specified suspension stroke depth, [lbf].

Cx.clk [=] Damping coefficient at specified suspension stroke depth, [lbf-sec/in].

Ft.clk [=] Averaged damping force integrated over specified stroke depth, [lbf].

Ct.clk [=] Averaged damping coefficient integrated over specified stroke depth, [lbf-sec/in].

Suspension operation with base valve clickers wide open:

U.wo [=] Suspension velocity with the base valve compression clicker set at the wide opened position. Mid-valve rebound clickers are set at position requested on the MVc input sheet. If you want to evaluate the effect of rebound clicker position on compression damping you can re-run the calculations with the rebound clicker on the MVc sheet set at different positions and compare the results, [in/sec].

Pr.wo [=] Fluid pressure in the rebound chamber with the base valve compression clickers wide opened, [psia].

Ft.wo [=] Averaged damping force integrated over stroke depth with the base valve clickers wide open. Mid-valve rebound clickers are at the position specified on the MVc tab. [lbf].

Ct.wo [=] Averaged damping coefficient integrated over specified stroke depth with the base valve compression clickers wide opened, [lbf-sec/in].

Suspension operation with the base valve clickers closed:

U.clsd [=] Suspension velocity with the base valve compression clicker closed. The rebound clicker is set at the position requested on the MVc input sheet, [in/sec].

Pr.clsd [=] Fluid pressure in the rebound chamber with the base valve compression clickers closed, [psia].

Ft.clsd [=] Averaged damping force integrated over stroke depth with the base valve clickers closed, [lbf].

Ct.clsd [=] Averaged damping coefficient integrated over specified stroke depth with the base valve compression clickers closed, [lbf-sec/in].