Removing the ISO FLEX insert is a simple process that only takes a few minutes. Start by removing the seatpost and seat collar. Next, using a Shimano Hollowtech II bottom bracket tool (we recommend the genuine Shimano TL-FC32 Bottom Bracket Tool), unscrew the lock ring counter clockwise and remove the lock ring and washer from the frame. Reinstall the seat collar, seatpost, and tighten the collar bolt. Gently rock the saddle back and forth while pulling up until the ISO FLEX insert assembly slides out of the frame. Loosen the collar and remove the insert from the seatpost. To reinstall, lightly grease the outside of the insert and slide it into the frame. Reinstall the washer and lock ring by turning it clockwise by hand until it bottoms out on the insert. Then, using the TL-FC32 Bottom Bracket Tool, snug down the lockring, reinstall the seat collar, insert the seatpost to your desired height and tighten the collar bolt to 5 Nm. For more detailed instructions with photos please see our tech document under the Tech Specs tab.