Headsets & Compression
Headsets on freestyle scooters are no different to those on BMX bikes. Those scooters take a 1 1/8" sized headset. A threaded headset is used for a threaded fork only. Their main use is for those usually running the stock forks. Threadless headsets are used with a compression system on threadless forks such as SCS (Standard compression system), HIC (Hidden internal compression system, which requires oversized bars) or ICS (Inverted compression system). The compression used on threaded forks is a locknut, that can be taken off a stock fork. Threadless headsets are used to accommodate threadless forks, which were created because threads compromise the strength of the fork tube.
- Standard Compression System (SCS)
- - scs clamp, compression bolt, starnut, headset cap, shim (use with thin bar)
The SCS resembles an oversized clamp but internally works much like a bicycle stem. There are two slots to fit the bars and fork, the smaller of which is located on the bottom and is for the fork. A starnut is installed into the forks and the SCS is placed over the fork tube. The compression bolt is screwed into the headset cap and then into the starnut. The cap is caught on the lip that is located internally in the SCS. The bars are placed into the top slot and bolts externally located on the SCS are tightened to act as a clamp.
Inverted Compression System (ICS)
- compression bolt, starnut, headset cap
A Starnut is installed into the bars. A compression bolt is screwed into a headset cap and is placed into the fork tube from below. It is then screwed into the starnut located in the bars. The headset cap is larger than the inner diameter of the fork tube and so catches and compresses.
Hidden Internal Compression system (HIC)
- compression bolt, headset cap, starnut, compression shim
A starnut is installed into the fork tube. a compression shim is placed over/around the fork tube and the compression bolt is screwed into the top of the fork tube through the headset cap and into the starnut. The shim is the compressor, as the headset cap is pushing down on the shim, the shim intern pushes down on the headset. Using HIC requires oversized bars and a bigger clamp.
- Main manufacturers: RAD, Madd Gear
- Thread Lock Compression (TLC)
A HIC-like compression system/fork made by Phoenix Pro Scooters, which involves the fork and compression shim to screw on together.
- Integrated Headset Compression (IHC)
A HIC-like compression system/fork made by Envy/Blunt Scooters, which fork column is narrow so that standard sized bars fit on the compression shim.
Borrowed with thanks from Wikipedia