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Bosch Smart System (BES3)Which replacement battery fits a Trek Rail 9 (Gen 4, 2023 on)?
The replacement battery that fits a Trek Rail 9 (Gen 4, 2023 on), the charger it uses, and what not to buy.
Fits with the Bosch PowerTube 750 (smart system). A Trek Rail 9 (Gen 4, 2023 on) runs the Bosch Smart System (BES3), so the replacement battery is the Bosch PowerTube 750 (smart system) (750 Wh, 36 V, BES3).
| Bike | Trek Rail 9 (Gen 4, 2023 on) |
|---|---|
| Drive system | Bosch Smart System (BES3) |
| Battery that fits | Bosch PowerTube 750 (smart system) (750 Wh, 36 V, BES3) |
| Charge port | Bosch smart-system round charge port |
| Charger | Bosch Standard Charger 4A (smart system) |
The Gen 4 Trek Rail runs the Bosch Performance Line CX smart system (BES3), so it takes a smart-system PowerTube, commonly the 750 Wh.
A pre-2023 Rail on eBike System 2 uses a BES2 PowerTube 625 instead, which will not fit the smart-system frame. Check the display for smart-system branding.
Sources: Urban Arrow Service Center, Differences between Bosch eBike System 2 (BES2) and Smart System (BES3) · Qiolor, Bosch e-bike motor compatibility explained · Bosch eBike Systems, PowerTube and CompactTube batteries · Clever Cycles, Bosch Standard Charger 4A Smart System