Filters
Clear- Ahead: (Threadless) Suitable for threadless forks. The most widespread system on modern bicycles.
- Threaded: (Threaded/Screw-on) Suitable for forks with threading at the top of the steerer tube. Usually found on older or city bikes.
- 1 1/8: The most common diameter on modern bicycles, for forks with a constant diameter.
- 1 1/8 - 1 1/4: (Tapered) Conical steerer with top part 1-1/8" and bottom 1-1/4".
- 1 1/8 - 1 3/8: (Tapered) Tapered steerer with a top diameter of 1-1/8" and a bottom diameter of 1-3/8", a less common standard.
- 1: Suitable for forks with a 1-inch steerer tube, typically found on older or city bikes.
- 1 1/8 - 1.5: (Tapered) Conical steerer where the top is 1-1/8" and the bottom is 1.5", commonly found on modern MTBs.
- 1 1/8 - 1 1/2: (Tapered) Conical steerer with top part 1-1/8" and bottom 1-1/2".
- 1.5: Larger steerer tube diameter for increased stiffness, mainly in MTB or downhill bikes.