FSA Direct Mount E-Bike Chainring 34T | Bosch Gen 4 | Megatooth A Steel | 55mm Chainline | ED Black (WB478B)
Description
FSA Direct Mount E-Bike Chainring 34T | Bosch Gen 4 | Megatooth A Steel | 55mm Chainline | ED Black (WB478B)
The FSA Direct Mount E-Bike Chainring is a 34 tooth steel chainring made for Bosch Gen 4 eBike drive units. It uses FSA’s Megatooth A narrow wide tooth profile to keep your chain secure under the high torque an eBike motor delivers. It has a 55mm chainline and an ED black finish, and it’s a dependable replacement or upgrade for riders who put their drivetrain through hard use. The FSA part number is WB478B.
Built for Bosch Gen 4 Drive Units
eBike drivetrains place far more stress on a chainring than a standard bike does, so a matched, durable part matters. This chainring uses a direct mount interface, so it fits straight to the Bosch Gen 4 drive unit without a separate spider or crankset. The 34T size suits riders who want a good balance of climbing ability and top speed.
Megatooth A Chain Retention
FSA’s Megatooth tooth profile alternates narrow and wide teeth to match the inner and outer links of your chain. The result is better chain retention, which helps reduce the chance of dropped chains over rough trails, big hits, and the sudden power delivery of a motor.
Strong Steel, Clean ED Black Finish
Steel gives the chainring long wear life against the extra load of motor assisted riding. The ED black finish adds a durable, clean look that suits modern eMTB and eBike builds.
Wide Drivetrain Compatibility
This chainring suits 10 and 11-speed drivetrains, and non-Shimano 12-speed drivetrains. Please check that your chain and cassette match before ordering.
Key Features
- FSA direct mount eBike chainring, part number WB478B
- 34 tooth
- For Bosch Gen 4 drive units
- Megatooth A narrow wide tooth profile for chain retention
- Steel construction
- 55mm chainline
- ED black finish
- For 10 and 11-speed drivetrains, and non-Shimano 12-speed drivetrains
Please note: This chainring is specific to Bosch Gen 4 direct mount drive units. Please confirm your bike’s drive unit, chainline, and drivetrain before ordering, or contact our team and we’ll help you check the fit.
