ACR Compatible Headset Adapters

V3 Adapters

V3 products are available on here on Etsy

Why do you want it?

If you operate an electronic shifting and hydraulic brake system and are seeking a lower-stack (by 4mm-5mm) solution that uses OEM internals and commonly available split spacers.

You are looking for a system that can pass hydraulic couplers or compression nuts through the headset for easier maintenance.

You're comfortable forgoing additional contact seals beyond those present on the bearing.

What is it?

This product consists of two parts: a Dust Cover and Stem Adapter. It must be used with a Deda DCR compression ring (not included) in either of the following formats:

- A 36-degree version to fit 36x45 41/52mm or ec44/40 headset bearings
- A 45-degree version to fit 45x45 41/52mm headset bearings

FSA ACR split spacers can be utilized with this system.

Dust Cover

This part interfaces with the Deda DCR C-shaped Compression ring and FSA ACR split spacers. It should also fit directly onto the Vision ACR Carbon stem and ACR series integrated bars. Two versions of the base plate are in testing: one for recessed bearings and another for non-recessed bearings.

Neither design includes a functional second seal, relying on the bearing seals for weatherproofing.

Recessed has 5mm and 6.5m of stack

Non recessed version adds 8.5mm of stack

Stem Adapter

These adapters allow FSA NS ACR stems, FSA/Vision SMR stems, or -17 Kalloy Uno 1 1/8-inch stems to connect either to the ACR split spacers or to the Base Plate. They enable M8, M9, and 10mm fittings used on hydraulic brakes to pass through, simplifying headset and fork maintenance.

NS ACR

SMR

-17 Kalloy Uno

V3 products are available on here on Etsy

V2 Adapters

Designed for direct interface with the FSA NS ACR stem without needing an adapter, V2 has been produced and in use since August 2022. Custom designs provide specific stack configurations and while split spacers add up to 10mm adjustability.