MCRIDER007
Well-known member
The FJR GEN2 shock uses two separate springs, the top spring only has about 1.5 coils of very wide coils and is rated at over 1800 lbs/in (it will never bind), the lower spring has about 4 coils and is rated at about 710 lb/in and it also will not not bind because the shock will run out of available travel (and bottom) before that happens. When the shock is in the soft position, both springs are in the spring series and all 5.5 coils are active. When the shock is in the hard position the top (short) spring is locked out of the spring series and only the 4 coils on the bottom spring are active, effectively raising the spring rate. The shock does not bottom because the springs bind, it bottoms because it runs out of internal travel. Each spring has a base preload that cannot be adjusted.
The ES has a pretty conventional single spring shock except that it is using a small electric motor compress the spring to change preload and a second motor to change the damping by adjusting the oil flow to the internal shim stacks. The single spring has a base preload that can be increased electronically in four steps and ES also changes the damping when the preload is changed to balance the system. That damping can then be changed to as many as 21 different settings at the rider's discretion.
The differences between the shocks is that the GEN2 has two very different spring rates (about 530 and 710 lb/in) but no preload/ride height adjustments. Each setting is going to have its own unique ride height with any given load. The ES is going to only have one spring rate (maybe 685 lb/in) but 4 different preload/ride heights (covering an 8mm range) for any given load. Preload normally is used to as a backdoor way to increase ride height (if a ride height adjuster is not available) and keep steering geometry consistent with different loads but can also be used to prevent bottoming by increasing the amount of available travel and allowing the spring's total compression to be greater than it was before. Preload does not change the spring rate although it may make the spring feel stiffer when you bounce on the seat in a showroom. Preload does not change the total amount the spring will be compressed after the rider's weight is added, just the amount that the spring will compress before the rider's weight is added. Since the total amount of spring compression does not change because of preload, the same part of the spring is used during normal riding and the ride quality should be the same.
A too light of spring and/or not enough preload adjustment can result in too much sag (which effects steering geometry) and excessive bottoming in addition to poor handling and ride quality and most suspension tuners recommend using a spring large enough that the desired sag can be achieved with about 10 mm of base preload.
The ES has a pretty conventional single spring shock except that it is using a small electric motor compress the spring to change preload and a second motor to change the damping by adjusting the oil flow to the internal shim stacks. The single spring has a base preload that can be increased electronically in four steps and ES also changes the damping when the preload is changed to balance the system. That damping can then be changed to as many as 21 different settings at the rider's discretion.
The differences between the shocks is that the GEN2 has two very different spring rates (about 530 and 710 lb/in) but no preload/ride height adjustments. Each setting is going to have its own unique ride height with any given load. The ES is going to only have one spring rate (maybe 685 lb/in) but 4 different preload/ride heights (covering an 8mm range) for any given load. Preload normally is used to as a backdoor way to increase ride height (if a ride height adjuster is not available) and keep steering geometry consistent with different loads but can also be used to prevent bottoming by increasing the amount of available travel and allowing the spring's total compression to be greater than it was before. Preload does not change the spring rate although it may make the spring feel stiffer when you bounce on the seat in a showroom. Preload does not change the total amount the spring will be compressed after the rider's weight is added, just the amount that the spring will compress before the rider's weight is added. Since the total amount of spring compression does not change because of preload, the same part of the spring is used during normal riding and the ride quality should be the same.
A too light of spring and/or not enough preload adjustment can result in too much sag (which effects steering geometry) and excessive bottoming in addition to poor handling and ride quality and most suspension tuners recommend using a spring large enough that the desired sag can be achieved with about 10 mm of base preload.
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