We get this question quite frequently from riders looking to upgrade their Shimano EP motor. And while it might seem like a serious undertaking—well, it kind of is—it can definitely be simplified and made a whole lot less scary. Don’t worry, we’ve already asked AI to break it down for you, so you don’t have to!
PHYSICALLY (fit?) - The Easy Part
Thankfully, in Shimano’s infinite wisdom, the motor mounting points on both motor systems are completely identical! This means no crazy frame modifications or special tools/adapters are required if you’re looking to upgrade to the EP801. PHEW!
THE E-OVERHAUL - The Hard Part
This is where things can get messy real quick. Grab a nice frosty bevvy of your choosing, maybe a lil snack, and strap in—we’re deep diving into the wiring and all the parts you will need to make the conversion happen.
To make this conversion possible and way easier, we’ve compiled a definitive cheat sheet of the various Shimano components you will need to replace vs. what carries over perfectly:
| Component Type | EP800 (Old System) | EP801 (New System) | Swap Requirement |
| Drive Unit | DU-EP800 w/o Cover | DU-EP801 w/o Cover US | Must Replace. |
| Drive Unit Cover | DC-EP800 Left | DC-EP801 Left | Must Replace. The EP801 requires the updated left-side motor cover. |
| Battery | Darfon 720Wh EP800 Integ. | Darfon 720Wh Integrated EP801 | Must Replace. |
| Battery Mount | Darfon EP800 Mount | Darfon EP801 | Must Replace. Required to interface with the new EP801 battery. |
| Display Unit | SC-E7000 | EM800AD | Must Replace. The old SC-E7000 display unit must be upgraded to the new EM800AD standard. |
| Mode Switch | SW-E7000-L | SW-EM800-L | Must Replace. Moved from E7000 to EM800 to match the new display. |
| Power Button | Darfon Power Button | Shimano EW-SW300 | Must Replace. Moves from a Darfon-specific button to the Shimano EW-SW300 system. |
| Wiring | EW-SD50 + Adapter | EW-SD300 | Must Replace. Complete elimination of the old SD50 wires and adapters. |
| Secondary Wiring | EW-SD300 | EW-SD300 | Must Replace. Length requirements change based on the new wire routing. |
| Speed Sensor | N/A | N/A | Keep. The speed sensor carries over perfectly. |
| Charge Port & Charger | N/A | N/A | Keep. Darfon charge port, adapter, and 4A Smart-Plus Charger are identical across both. |
Need any extra help or have questions about your specific build? Head over to www.santacruzbicycles.com or stop by your local authorized dealer to get your rig completely dialed in!