SpeedBox 1.4 B.Tuning for Bosch SX | Smart System + Rim Magnet

Built for the lightweight Bosch Performance Line SX. The SpeedBox 1.4 B.Tuning removes the 25 km/h assistance limit on SX-powered Smart System bikes running rim magnets, with adjustable speed limit settings via Bluetooth.

Compatible with: Bosch Performance Line SX Gen 4 motors, models BDU3142 and BDU3143. If your SX bike has motor model BDU3144/3145, you need the SpeedBox 1.5 instead — check the Flow app or ask us to confirm your motor model before ordering.

Keyed connectors, reversible install, lifetime functionality warranty from SpeedBox. Fitting available at the Grace and Pace workshop, Alphington.

Important: private property use only — a tuned e-bike must not be ridden on public roads, paths or trails in Australia. Tuning may affect your bike manufacturer's warranty. The rider is responsible for complying with all applicable laws.