What is the difference between threaded, threadless, internal, and integrated headsets?
• Threaded headset cups press directly into the frame. The fork used for threaded headsets is threaded, and a large nut installed on the steerer tube is used to preload the bearings.
• Threadless headset cups also mount directly into the frame, but a star-nut or similar compression device installed in the fork is used to preload the bearings.
• Internal headsets are functionally similar to threadless headsets. The main difference is that internal cups press almost completely into the frame. These are often preferred for their low stack height and clean look.
• Integrated headsets are becoming more and more popular. With integrated headsets, a bearing (usually a sealed cartridge unit) s directly into the frame eliminating the need for cups. With integrated headsets, it is not necessary to press cups into your frame, but it is important that the headtube be professionally machined to the proper dimensions to ensure smooth operation.