SPIDER Automation | 420 Chain Sprocket for E-Bike | 28T, 116mm Outer Diameter & 64mm Inner Bore
Product Overview
The 420 28T Sprocket is a mechanical power-transmission component designed for compatible electric bicycle and electric vehicle chain-drive systems. Its 28-tooth profile is intended for use with a matching 420 chain, providing the chain engagement required to transfer rotational power within a suitable drivetrain.
The sprocket features a 116mm outer diameter, 64mm inner mounting bore and 6mm thickness. The specified mounting interface is intended for a four-hole gearless freewheel arrangement with a 95mm outer-diameter interface.
This sprocket can be considered for compatible e-bike, tricycle and custom electric vehicle transmission projects. Correct selection depends on matching the 420 chain, sprocket mounting pattern, freewheel interface and overall drivetrain geometry.
Technical Features & Functional Characteristics
- 420 Chain Profile: Designed for engagement with a matching 420 chain. The chain and sprocket must use the same chain standard for correct meshing.
- 28-Tooth Configuration: Provides a 28T tooth count for selecting a suitable chain-drive transmission ratio.
- 116mm Outer Diameter: Defines the external sprocket diameter for compatible drivetrain layouts.
- 64mm Inner Mounting Bore: Provides the specified internal mounting dimension for the intended freewheel interface.
- Four-Hole Freewheel Interface: Intended for a compatible gearless freewheel mounting arrangement with a 95mm outer-diameter interface.
- 6mm Plate Thickness: Provides the specified sprocket thickness for the mechanical assembly.
- Electric Mobility Drivetrain Use: Suitable for compatible electric bicycle, tricycle and custom electric vehicle chain-drive systems.
420 Chain Compatibility & Transmission Function
A chain sprocket transfers rotational motion through engagement between its teeth and the links of a compatible chain. The 420 chain standard must match the sprocket tooth profile to maintain correct engagement and reduce the risk of chain skipping or premature wear.
The 28T sprocket works with a matching 420 chain to form part of a chain-driven transmission. The final speed and torque relationship depends on the tooth count of the mating sprocket, motor speed, wheel size and the overall drivetrain configuration.
A thicker chain and sprocket system should not automatically be treated as suitable for a particular vehicle speed or power level. Actual operating limits depend on the chain, sprocket material, mounting strength, alignment, tension and complete drivetrain design.
Mounting Interface & Compatibility
The sprocket is intended for a four-hole gearless freewheel mounting arrangement with a stated 95mm outer-diameter interface. The 64mm inner mounting bore and four-hole pattern must match the mating component before installation.
The four-hole arrangement, hole spacing and fixing dimensions are important for correct mounting. The stated 95mm interface dimension alone does not establish compatibility with every four-hole freewheel assembly.
Applications
- Electric Bicycle Drivetrains: For compatible e-bike chain-drive systems using a 420 chain and matching freewheel mounting arrangement.
- Electric Tricycles: For suitable three-wheel electric vehicle transmissions with a compatible four-hole mounting interface.
- Electric Rickshaws: For compatible chain-driven rickshaw projects requiring a 420 sprocket assembly.
- DIY E-Bike Conversions: For custom bicycle electrification projects using a matching motor, chain and driven sprocket.
- Electric Scooter Projects: For suitable chain-driven scooter configurations with matching drivetrain dimensions.
- Electric Utility Carts: For compatible chain-drive transmission layouts in small electric carts.
- Custom Electric Vehicles: For suitable motor-driven vehicle projects using a 420 chain transmission.
- Drivetrain Replacement: For replacing an existing 28T sprocket when chain size, mounting pattern and dimensions match.
- Mechanical Workshop Projects: For prototyping and assembling compatible chain-driven power-transmission systems.
Package Includes
| Quantity | Component |
|---|---|
| 1 | 420 Chain Sprocket – 28T |
Product Specifications
| Parameter | Specification |
|---|---|
| Product Category | Mechanical Power-Transmission Component |
| Item Type | Chain Sprocket |
| Chain Standard | 420 |
| Number of Teeth | 28T |
| Outer Diameter (OD) | 116mm |
| Inner Diameter (ID) | 64mm |
| Sprocket Thickness | 6mm |
| Mounting Arrangement | Four-hole gearless freewheel interface |
| Compatible Freewheel Interface | 95mm outer-diameter gearless freewheel arrangement |
| Intended Transmission | 420 chain-drive system |
| Intended Applications | Compatible e-bikes, tricycles, electric rickshaws and custom electric vehicles |
| Package Quantity | 1 sprocket |
Installation & Operating Recommendations
Install the sprocket only in a drivetrain with a matching 420 chain and compatible four-hole freewheel mounting interface. Correct mounting, chain alignment and tension are essential for smooth power transmission and reduced mechanical wear.
- Match the Chain Standard: Use a 420 chain designed to engage with the sprocket tooth profile. Do not substitute a different chain standard based only on similar appearance.
- Confirm Mounting Dimensions: Check the 64mm inner bore and the mating freewheel’s mounting geometry before installation.
- Check the Four-Hole Pattern: Match the fixing-hole positions and spacing with the gearless freewheel assembly. The 95mm interface diameter alone is not sufficient to confirm fitment.
- Use Suitable Fasteners: Select fasteners that match the mounting arrangement and secure the sprocket without interference.
- Align the Chain Line: Keep the sprocket aligned with the mating sprocket to reduce side loading and uneven chain wear.
- Set Chain Tension: Maintain appropriate chain tension according to the drivetrain design. Excessive tension can increase loads on shafts and bearings.
- Check Rotational Clearance: Rotate the assembly manually to ensure the sprocket and chain do not contact nearby components.
- Inspect During Maintenance: Periodically check sprocket teeth, chain condition, fasteners and mounting security.
