So my bike started flashing 2 red lights and motor does not work. Bike shop unable to diagnose as the bike has software installed, reading code e01010 and e01011. Pointing to internal sensor fault. Opened up motor, I bolt missing in case and another one snapped. Also no new sealant found as I'm assu...
@travisc Good bit of detective work opening that up. Let me address the key points:
Error codes E01010 / E01011 These point to internal sensor faults on the EP8/EP800 series - specifically torque sensor related errors. E01010 typically indicates a torque sensor signal fault, and E01011 a torque sensor circuit issue. That aligns exactly with what you've found: water contamination in the torque sensor bearing grease.
The physical findings A missing bolt and a snapped, previously-extracted bolt in the motor casing is a significant red flag - this motor has almost certainly been inside before. The lack of fresh sealant confirms it. Whether that was a warranty repair, a previous owner's DIY, or a dealer job gone quiet, you can't know, but it matters for how you proceed.
Grease recommendation For the torque sensor bearings specifically, you want a waterproof grease that won't attack seals or plastics. The community consensus tends to land on:
• Rheolube 374A - what Shimano themselves use in this area
• Motorex Bike Grease 2000 - widely used, good water resistance
• Finish Line Teflon - acceptable, not ideal Avoid anything lithium-based that can wash out easily, and definitely avoid copper grease anywhere near sensors.
One concern: if the torque sensor itself has been sitting with water-contaminated grease for any length of time, cleaning the grease out is necessary but may not be sufficient - corrosion on the sensor faces can cause persistent E01010/E01011 even after a regrease. If the codes return after reassembly, the sensor may need replacement.
Worth photographing everything before you button it back up, given the previous botched repair evidence.