Bike Yoke Revive Dropper Post The BikeYokes Revive features a non-IFP design because it is too difficult ?혀 if not impossible ?혀 to make a reliable design using an IFP. The Revive only requires two dynamic seals in the hydraulic circuit (RS Reverb, KS LEV and Fox Transfer use four dynamic seals) with those two seals being the ones that are known to cause the least problems in sealing application: The inner shaft sealing and the piston sealing for the lockout mechanism. The highly critical IFP is removed and with it the need of perfect concentricity and finish of the sealing surfaces of the tubes. The lack of an IFP also results in the smoothest action of any hydraulic drop-post on the market. Even Revive can get air somewhere where it does not belong. This can happen for example, when you actuate your seatpost for a few times, while its upside down. And here is where the patented Revive Reset Valve comes into play: The Revive valve is located underneath the seatpost-head (same as a Reverb and KS LEV for example) and serves as regular air-valve for pumping up the post. However, pushing the Revive valve opens ports between chambers and activates the Revive-function.