Interactive crossovers (sample apps) use a shim diameter that is larger than the shim stack clamp. The larger crossover diameter transfers force from the face shims directly into the high speed stack forcing the high speed stack to deflect before the crossover closes. Interaction with the high speed stack softens the crossover closure event.
Shim ReStackor analysis of an interactive crossover tested by MXScandinavia on Thumper Talk produces a crossover closure velocity of 60 in/sec. However, the MXScandinavia dyno could only test to shaft speeds of 40 in/sec.
The test illustrates a typical dyno frustration. At the velocity limit of the test no unusual behavior is observed. However, the crossover gap has not closed creating uncertainties the shock absorbers high speed performance.
Shim ReStackor helps relive those uncertainties with the capability to compute high speed shock absorber performance and evaluate crossover closure velocities and the effect of valve port flow restrictions that kick in beyond the limits of conventional dyno testing.
