This guide is written by the team at ProScooter.Shop — Georgia's dedicated freestyle scooter store in Tbilisi.
Why Compatibility Matters
Buying the wrong parts is the most common and most avoidable mistake in custom scooter building. A fork that does not match your compression system, or bars with the wrong diameter for your clamp, cannot be made to work — no matter how much you want them to.
This guide approaches compatibility from two directions: starting from the fork, and starting from the bars. Use whichever matches your situation.
Before we begin: this guide covers the three compression systems relevant to modern freestyle scootering — SCS, HIC, and IHC. Threaded and ICS systems are excluded — threaded forks are not suitable for trick riding, and ICS has effectively left the market.
Part One: Starting From the Fork
Most riders choose a fork first, then build around it. Here is what each fork type is compatible with.
SCS / HIC Forks
These two compression systems share the same fork — the steerer tube diameter is 28.7mm for both. The difference is in how you build around it.
One important detail: fork steerer tube length matters. A shorter steerer tube suits SCS best; a longer steerer tube is oriented toward HIC. However, with additional spacer rings, a long-steerer HIC fork can be assembled with SCS compression.
Building with SCS on a SCS/HIC fork:
- SCS clamp (with washer and compression bolt — always included with the clamp)
- Bars with no slit, external diameter 31.8mm or 34.9mm
- Note: some compact SCS clamps (e.g. AZTEK Pandora, TILT Sculpted) accept standard 31.8mm bars only — check compatibility before buying
Building with HIC on a SCS/HIC fork:
- HIC sleeve with washer and compression bolt (rarely included with the fork — purchase separately)
- HIC bar clamp, typically 2-bolt (1, 3, and 4-bolt variants exist — do not confuse with SCS)
- Bars with a slit, external diameter 34.9mm (oversized), material: steel or titanium only
| SCS | HIC | |
|---|---|---|
| Fork steerer diameter | 28.7mm | 28.7mm |
| Compression hardware | SCS clamp | HIC sleeve + separate clamp |
| Bar slit | Not required | Required |
| Bar diameter | 31.8mm or 34.9mm | 34.9mm only |
| Bar material | Steel, aluminium, titanium | Steel or titanium only |
IHC Forks
IHC forks have a narrower steerer tube (~25mm diameter) and are IHC-specific — they cannot be used with SCS or HIC without modification.
Building with IHC on an IHC fork:
- IHC collet with washer and compression bolt (typically included with IHC forks)
- HIC/IHC bar clamp, 31.8mm or 34.9mm depending on bar diameter
- Bars with a slit, diameter and material as follows:
- Steel bars: 31.8mm (standard diameter)
- Aluminium bars: 34.9mm (oversized diameter)
| IHC | |
|---|---|
| Fork steerer diameter | ~25mm |
| Compression hardware | IHC collet + separate clamp |
| Bar slit | Required |
| Bar diameter | Steel: 31.8mm / Aluminium: 34.9mm |
| Bar material | Steel or aluminium |
Part Two: Starting From the Bars
If you already have bars and need to find a compatible fork and clamp, use this table.
| Bar material | Bar diameter | Slit | Compression | Clamp | Fork |
|---|---|---|---|---|---|
| Steel | 31.8mm | Yes | IHC | HIC/IHC 31.8mm | IHC |
| Steel | 31.8mm | No | SCS | SCS (31.8mm or 34.9mm with shim) | SCS/HIC |
| Steel | 34.9mm | Yes | HIC | HIC 34.9mm | SCS/HIC |
| Steel | 34.9mm | No | SCS | SCS 34.9mm | SCS/HIC |
| Aluminium | 31.8mm | No | SCS | SCS (31.8mm or 34.9mm with shim) | SCS/HIC |
| Aluminium | 34.9mm | Yes | IHC | HIC/IHC 34.9mm | IHC |
| Aluminium | 34.9mm | No | SCS | SCS 34.9mm | SCS/HIC |
| Titanium | 34.9mm | Yes | HIC | HIC 34.9mm | SCS/HIC |
| Titanium | 34.9mm | No | SCS | SCS 34.9mm | SCS/HIC |
Note on aluminium bars: aluminium bars in standard 31.8mm diameter with a slit do not exist in the freestyle scooter market — there are no forks with a steerer tube narrow enough to accommodate them. If you encounter such bars, they are not suitable for a custom build.
The SCS Adapter: One Exception to the Slit Rule
Bars with a slit are normally incompatible with SCS — the clamp bolts would deform the bar at the slit point under clamping pressure.
The exception is the SCS adapter: a short insert placed inside the bar at the slit, reinforcing it from the inside. With an SCS adapter correctly installed, a slit bar can be used with SCS compression.
This is the only recommended workaround. Do not attempt other improvised solutions — they compromise structural integrity.
Common Mistakes to Avoid
Buying HIC bars for an IHC fork — HIC bars are oversized steel or titanium (34.9mm). IHC forks require steel 31.8mm or aluminium 34.9mm. The fork type determines which bars work, not just the outer diameter.
Assuming all SCS clamps accept all bar diameters — most standard SCS clamps accept both 31.8mm (with a shim) and 34.9mm bars. Compact or lightweight SCS clamps often accept 31.8mm only. Always check the clamp specification.
Using a long-steerer HIC fork with SCS without spacers — it will work, but the steerer tube will protrude above the SCS clamp. Add spacer rings to fill the gap before installing the clamp.
Quick Reference: Which System for Which Situation?
You want maximum strength and the easiest maintenance → SCS
You have oversized steel or titanium bars with a slit and want to save weight → HIC
You are upgrading a complete scooter or want the lightest modern build → IHC
You are building your first custom and are not sure → SCS. Widest compatibility, easiest to get right.
Still Not Sure?
Bring your parts list or your existing scooter to ProScooter.Shop at 11 Griboedov Street, Tbilisi. We will check compatibility and advise before you buy anything. You can also reach us via WhatsApp or Telegram at +995 595 417 489.
For a full explanation of how each compression system works, see our Compression Systems Explained guide.
Browse our full range of forks, bar clamps, and bars at ProScooter.Shop.
This article was last updated in April 2026. Compatibility standards in the scooter industry evolve — if you have spotted an error or have a question about a specific combination, get in touch.
