Today, we’ll delve into the world of compression systems to provide a comprehensive explanation of their components and help you determine the most suitable option for your needs.
What's a compression system?
In the scooter world, a compression system is the mechanism that tightens your headset, which essentially determines the possible combinations of fork, clamp, and bars.
The different systems
There are numerous different systems available, but mostly, three to four are currently in use, so we’ll focus on those instead of wasting our time on systems that you’ll likely never encounter.
IHC (Internal Hidden Compression)
The IHC system works with a shim located on the fork that tightens the headset. We could say that it’s a shim type compression system and is technically the lightest system in use.
IHC Bars
The IHC will work with any bars that have a slit and a standard internal diameter of 28mm, such as standard steel or aluminum bars. It’s one of the most widely used systems because it functions flawlessly with aluminum bars.
Here's the IHC bars we have compatible right now. Simply be sure that it has a slit! If not, choose the slit option in the modification menu and we'll do it for you!
IHC Clamps
Essentially, any clamp that isn’t SCS will fit, regardless of whether it has one, two, or even more bolts. The only requirement is that the inner diameter of the clamp matches the outer diameter of the bar. For instance, a standard clamp (or an oversized clamp with a shim) can be used for a standard bar, while an oversized clamp can be used for an oversized bar.
Here's the clamps that will fit IHC. Just be sure it includes a shim to fit standard sizes if the clamp is oversized. But the majority of them come stock with it now.
IHC Forks
The IHC forks will always come with everything you need to tighten your headset because the diameter of the fork tube isn’t necessarily standardized. This means that buying a compression ring or a shim separately might be difficult so it’s always included.
Here's all the IHC fork we have in stock!
Strong installation
Making a slit in a bar will inevitably weaken it but it's necessary for the IHC compression system. So you'll always want the fork tube to be higher than your slit in the bars. This will ensure less stress on the weakest part of the bar that is the top of the slit.
HIC (Hidden Internal Compression)
The HIC system works the same way as the IHC one, but oversized. Since the fork has more meat on it, it will be stronger but a bit heavier than the IHC.
HIC Bars
The HIC will work with any bars that have a slit and an oversized inside diameter, such as oversized steel or oversized titanium bars. However, aluminum bars will not fit on there.
Here's what we have in stock in HIC bars. Simply be sure that it has a slit! If not, choose the slit option in the modification menu and we'll do it for you!
HIC Clamps
Again, whether it has 1 or 2 bolts (or even that nonsense of having more…), any clamp that is not SCS and is oversized will do.
Here are the clamps that will fit HIC.
HIC Forks
A fork that fits SCS will also fit HIC because the diameter of the fork tube is the same. Therefore, you often see forks that can be used for both systems. However, some forks are specifically designed for each compression system due to the length of the tube. Forks labeled as HIC only have a longer tube, while SCS-specific forks have a shorter tube.
When choosing your HIC fork, ensure that it clearly states « HIC or SCS/HIC» somewhere on it. This should ensure that you get the right fork for your needs.
Here's the selection we have in stock. Just make sure it comes with a HIC compression shim or get one in our hardware section!
Strong installation
For exactly the same reason as the IHC system, making a slit in a bar will inevitably weaken it but it's necessary for the HIC system also. So you'll always want the fork tube to be higher than your slit in the bars. This will ensure less stress on the weakest part of the bar that is the top of the slit.
* That is especially important when using a titanium bar. We've seen to many big slit with SCS forks in the shop not to make a special mention.
SCS (Standard Compression System)
The SCS system is designed to tighten with the clamp instead of a shim. That’s why the SCS clamps are significantly larger than your IHC/HIC clamps. It’s one of the strongest systems available, but it also comes with a heavier weight and is slightly harder to adjust.
SCS Bars
The SCS system has a unique feature: any bar can be used, provided the inner diameter of your clamp can accommodate the outer diameter of the bar. A standard SCS (often referred to as LT) is designed to fit standard-sized bars only. However, an oversized SCS can accommodate both oversized and standard bars by using a shim.
The only essential requirement is a bar without a slit or with an SCS plug to eliminate the slit.
Since all the bars can fit, here's all that we have! Make sure it comes with a SCS plug if it has a slit and if not, buy one here!
SCS Clamps
SCS clamps are unique because they form the compression system. Most of them have four bolts, but we’ve seen lighter models with fewer bolts over the years.
Regardless of the number of bolts, the crucial setting to check while installing your SCS clamp is that the fork doesn’t stand higher than the inner edge of the clamp. If it does, it won’t tighten your headset, and you’ll need headset spacers to adjust it.
Here're all the SCS clamps we have in stock.
SCS Forks
As previously mentioned, a fork that fits SCS will also fit HIC because the diameter of the fork tube is the same. Consequently, you often see forks that can be used for both systems. However, some forks are specifically designed for each compression system due to the length of the tube. Forks labeled as HIC only have a longer tube, while SCS-specific forks have a shorter tube.
Therefore, when selecting your SCS fork, ensure that it clearly states « SCS » somewhere. This will ensure that you make the right choice.
Here's what we have in stock that will fit
Strong installation
To have the strongest set-up with your SCS, you'll want the fork tube and the bars to be as close together as possible. If there's too much of a gap, it will create stress in that area and weaken your set-up.
* Check out our blog specifically on SCS for tips and tricks.
ICS (Inverted Compression System)
That system, which was primarily used by Ethic DTC, has been discontinued since its inception due to Ethic DTC’s decision to switch to IHC for a simpler system. However, the ICS system stood out for its exceptional weight-to-strength ratio, which is why Ethic DTC has persistently advocated for its adoption as a standard by the majority.
The ICS system operated by incorporating a tread within the bar, either in the form of a starnut (aluminum bars) or a welded treaded part (steel bars). To tighten the headset, the compression screw was screwed from beneath the fork.
ICS Bars
The ICS system is compatible with any aluminum bar equipped with a star nut; if not pre-installed, you can purchase one separately. It can also be used with a standard steel bar featuring a welded tread. However, we strongly advise against using a regular star nut in a steel bar, as it tends to slip and loosen your headset.
Here are the bars that can fit ICS out of the box. Or you can grab an aluminum bar and ask us to add a starnut!
ICS Clamps
Again, whether it has 1 or 2 bolts (or even that nonsensel of having more…), any clamp that is not SCS and can fit. Just be sure it has the same inner diameter than the outside diameter of the bar.
Here's the clamps that will fit ICS. Just be sure it includes a shim to fit standard sizes if the clamp is oversized. But the majority of them come stock with it now.
ICS Forks
For that compression system, you’ll need a fork specifically designed for ICS. When Ethic DTC was still promoting their ICS system, a few brands offered ICS forks, but they’re almost nonexistent now. Just make sure you find the « ICS » acronym written on it!
Additionally, you’ll need an ICS screw, either the standard ICS screw or, more likely, the ICS-10 screw, which is the latest version and a special allen key.
When writing this blog, we didn't have any ICS fork left in stock and we doubt we'll have more. But if you need one, contact-us and we'll find one for you!
What's the best choice for you?
It all depends on your specific needs and preferences. The choice of compression system ultimately depends on the components you already have to ensure compatibility or on your riding style and preferences.
For instance, if you prioritize the lightest scooter possible, IHC might be the best option for you if you plan on going (or already have) an aluminum bar.
But if you’re not concerned about weight but want the tallest bars for street-style riding, SCS could be a better fit while also giving the most versatility of bar choices.
If you plan on going with a titanium bar that offers the best strength-to-weight ratio, HIC would be the best choice.
Hope this blog helped you out.
Till next time!
