FSA Orbit 1.5 ZS (NO.57E) Headset – Tapered 1 1/8"–1.5"
Part Number: 121-0501
EAN: 4712010050260
Product ID: 113355
Brand: FSA
Type: Headset
Model: ORBIT 1.5 ZS
Version: NO.57E
The FSA ORBIT 1.5 ZS (NO.57E) is a semi-integrated (Zero Stack / ZS) headset designed for 1 1/8"–1.5" tapered steerer tubes. It is suitable for bicycle frames with the specified upper and lower head tube dimensions.
The headset uses Angular Contact Ball Bearings (ACB) with a 36°/45° configuration. Their optimised internal construction allows the bearings to handle radial and axial loads simultaneously, providing precise and smooth steering as well as long-term durability.
The durable, CNC-machined aluminium components and precision bearing system make this headset a reliable choice for road, MTB and urban bicycles.
Key Features
- Designed for 1 1/8"–1.5" tapered steerer tubes
- Semi-integrated Zero Stack (ZS) design
- Press Fit construction
- Angular Contact Ball Bearings (ACB)
- 36° / 45° bearing angles
- Durable CNC-machined aluminium construction
- Precise and smooth steering
- Suitable for road, MTB and urban bicycles
- Compact 8 mm stack height
Technical Specifications
- Brand: FSA
- Model: ORBIT 1.5 ZS
- Version: NO.57E
- Product Type: Headset
- Integration: Semi-integrated / Zero Stack (ZS)
- Steerer Compatibility: 1 1/8"–1.5" tapered
- Upper Head Tube Outer Diameter: 50 mm
- Lower Head Tube Outer Diameter: 62 mm
- Upper Head Tube Inner Diameter: 44 mm
- Lower Head Tube Inner Diameter: 55.95 mm
- Upper Steerer Diameter: 28.6 mm
- Lower Steerer Diameter: 38.1 mm
- Upper Bearing: 41 × 30.2 mm
- Lower Bearing: 51.8 × 40 mm
- Bearing Angles: 36° / 45°
- Upper Bearing Height: 6.5 mm
- Lower Bearing Height: 8 mm
- Stack Height: 8 mm
- Material: Aluminium
- Colour: Black
- Weight: 124.6 g
- EAN: 4712010050260
- Part Number: 121-0501
Materials and Shapes
ACB Angular Contact Bearings
The 36°/45° Angular Contact Ball Bearings are designed to handle radial and axial loads simultaneously. This contributes to precise steering, smooth operation and long service life.
Aluminium Cups
The durable CNC-machined aluminium components provide rigidity and precise positioning within the bicycle frame’s head tube.
Compatibility and Important Information
The headset is suitable for frames with:
- Upper Head Tube: 44 mm inner / 50 mm outer diameter
- Lower Head Tube: 55.95 mm inner / 62 mm outer diameter
- Steerer: 1 1/8"–1.5" tapered
Important: When using a fork with a straight 1 1/8" steerer, the FSA Crown Race H6089 must be purchased separately.
Applications
The FSA ORBIT 1.5 ZS headset is ideal for:
- Road bicycles
- MTB bicycles
- Urban and trekking bicycles
- Bicycles with tapered steerer tubes
- Frames with 44/50 mm upper and 55.95/62 mm lower head tube dimensions
In Practice
The FSA ORBIT 1.5 ZS combines a semi-integrated Zero Stack design with precision ACB bearings to provide reliable and accurate steering performance. Designed for 1 1/8"–1.5" tapered steerer tubes, it is well suited to modern road and MTB bicycles, while its low 8 mm stack height allows for a compact installation.
