Freestyle scooter forks differ mainly according to the type of compression that holds the entire scooter together and compatibility with the wheel. Almost all forks are made of aluminum and can be referred to as 8STD and 12STD. In most cases, the fork is 8STD, which means it has an 8mm axle hole and also uses an 8mm axle. However, it is possible that some taller and more powerful scooters will use the 12STD system, which means that the axle is 12mm and therefore the wheel must be 12STD. There are several types of compression, and the most commonly used are screw compression, IHC, ICS-10, HIC, and SCS.
Lower and smaller scooters can be equipped with threaded compression, which means that the entire fork is one big thread, and in this case the compression is created by a large bolt nut. You will find such forks rarely as a separate part, so if you already have a threaded fork and would like another one, make sure that the other components with a different type of compression will fit.
IHC forks are mainly used in skatepark completes, as they are primarily light. The compression here is created thanks to a shim (a high pad with a cut along the height), a cap and a compression screw that is tightened directly into the fork (the fork has a built-in thread in the body). For this type, a classic clamp is used to tighten the handlebars to the fork. IHC forks are compatible with smaller diameter handlebars (Standard).
HIC and SCS forks are often combined in one product, as they are the same diameter (oversized), but differ in the compression method. The HIC system is almost the same as the IHC, the only difference is that the HIC fork is thicker, therefore it is compatible with steel and titanium handlebars. The SCS system does not use a shim, but an SCS clamp is placed directly on the fork, which then creates compression with the cap. SCS and HIC forks are stronger but often heavier.
ICS-10 forks are currently mainly manufactured by Ethic. The difference is simple, the fork does not have a thread in it, but uses a special screw that is inserted from below and is screwed directly into the handlebars, which have a built-in ICS hedgehog. The fork can also be used without such handlebars, but the same system as the IHC must be used. So insert the compression screw from the bottom side and screw the nut on top of the shim.
When choosing a fork, we recommend paying attention to compression (which you are looking for and which your other components require) and wheel compatibility (width, diameter, axle size).