Rohloff Sensor Magnet for 2.3 mm Brake Rotors – petrol
Rohloff E-14 Sensor Magnet for 2.3 mm brake rotors (8819, petrol) – a speed sensor magnet that fits into a Rohloff Speedhub brake rotor and gives an e-bike's wheel speed sensor its signal.

Why the rotor magnet?
Mounts in the rotor. The magnet sits in a cavity of the Rohloff brake rotor – no extra spoke magnet needed.
For 2.3 mm rotors. Rohloff makes the magnet in different versions for each rotor thickness; the petrol one is for 2.3 mm.
For e-bike speed sensors. Gives the e-bike's wheel speed sensor its signal; retailers list it as compatible with the MY21 Bosch speed sensor.
Colour-coded. Grey for 1.8 mm, black for 2.0 mm, petrol for 2.3 mm rotors – easy to tell apart.
Who is it for?
- E-bike riders with a Speedhub. A clean speed sensor solution on the brake rotor.
- Workshops building Speedhub e-bikes. The matching part for each rotor thickness.
Compatibility
| Rohloff article no. | 8819 |
|---|---|
| Colour | petrol |
| Rotor thickness | 2.3 mm |
| Matching rotor | Rohloff t2.3 mm rotor (8278/8279/8280) |
| Other versions | Grey 1.8 mm (8818), black 2.0 mm (8817), petrol 2.3 mm (8819) |
Frequently asked questions
How do I pick the right magnet?
Measure or check your rotor thickness. This petrol magnet is for 2.3 mm Rohloff rotors only.
Does it work with my e-bike system?
Retailers list it for the MY21 Bosch speed sensor. For other systems, please ask us before ordering.
Is the 2.3 mm rotor common on e-bikes?
The 2.3 mm Rohloff rotor comes in 180, 203 and 220 mm – sizes often chosen for heavy e-bikes and cargo bikes. The petrol magnet matches it.
About Rohloff
Rohloff AG is a German engineering company based in Fuldatal near Kassel. It makes the SPEEDHUB 500/14, the 14-speed gear hub that touring, trekking and expedition riders have trusted for decades, and is also known for its workshop tools, chain and sprocket wear gauges and Oil of Rohloff chain lubricant.
BoodaBike (Massive Bikes, Budapest) is an official Rohloff service centre, trained by Rohloff, and an official European distributor of Rohloff hubs and parts. Everything we sell is genuine Rohloff, and we are happy to help you pick the right part.
