Scooter Compression and Clamps
This is the most complicated component on a scooter and where people get the most confused.
There are 4 main compression systems. SCS, HIC, IHC & ICS. Depending on which part of the world you live on and the preference each scooter rider has, everyone rides the compression system that bests suits them. So what’s the difference between them and what does it all do?
Compression and clamps hold the fork and handle bar in place and aligned, and also firmly in place through the headset and deck. The result is the handlebars are effectively ‘hard connected’ to the fork and front wheel while it can all spin freely around the deck of the scooter. Adjustments are always needed as it’s mechanical and takes a beating as well !
So here is some more info.
SCS – A SCS clamp is either a triple or quad bolt clamp with some internal extras. This clamp does 2 functions. The bottom half has the standard size fork inserted, and then a cap & screw which will squeezes the fork up to hold the fork in place to the headset and deck. The top half will have the bars inserted . The bolts on the outside of the clamp then squeeze around the outside of the fork and the bar to keep it all aligned for the wheel and handlebar.
SCS is simple to work with and strong. It give maximum bar height as the bottom of the bar only goes in half way for this to all work properly.
HIC – HIC requires an oversized bar, an HIC shim, an Oversized clamp & a standard fork. The HIC shim is a sleeve that is placed over the top of the fork, then a cap & screw is tightened to squeeze the fork up to hold the fork in place to the headset and deck. Then the next step is putting a bar over the top of the shim (which is why you need an oversized bar to fit). The bolts on the outside of the oversized clamp then squeeze around the bar, squashing it firmly against the fork and shim, to keep it all aligned for the wheel and handlebar.
If you’re not a fan of the bulkier look of an SCS & want to save weight then HIC is the better option for you. Please note the bottom of the bar must have a slit cut in it to work.
IHC – IHC is basically the exact same as HIC, but its with a narrow gauge fork. This reduces weight and changes some of the requirements of components as frequently the fork includes the required compression fittings like the shim sleeve, cap, screw and also a special sized ring to adapt the fork into the headset bearing.
This is most common on many complete out of the box scooters due to costs and weight. Its a great system, very popular and some convertors also exist to enable use of other components with this system.
ICS – ICS compression is the least common compression system. It is more complicated to work with than other compression systems, although it’s the lightest compression system. ICS can be quite limiting with product choices, but it’s a good compression system.
You will need a starnut located inside your handle bars, and you need an Standard size fork that is ICS compatible. Basically , a long bolt feeds through the bottom of the fork & tightens up into the starnut inside the bars. This pulls the fork up and the bar down squeezing the whole lot firmly into the headset bearings which allows the bar and fork to spin around. A Normal clamp then squeezes the handle bar around the fork so it doesn’t slip.