Thanks for your guys help.
Below are our suggestions: (I quote some sentences from KMac)
1. Don't allow the servo saver to twist (by adjusting it properly and firmly) and it will operate correctly. The servo saver has to be tight to function correctly. When it is tight the unit can't physically twist on the rails.
Adjust towards the front to tighten. It doesn't take a lot, either. When the tension is proper it will take a little effort to move the servo saver back and forth, BUT it should be smooth and not jerky or get progressively tighter. This is why standard servos don't cut it with this steering system.
2. Please remember to use dust foam on the servo saver & use a drop of silicone oil on each foam. These foams are very very important to prevent the dust from going inside the metal sleeve position.
3. Please make sure that the servo saver is really a servo saver. If it works, there shouldn't be any servos broken. Please don't overtighten the servo saver tension spring. If you overtighen the spring, there will be no "Saver" function.
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