If your eMTB’s cranks turn backwards but the chain stays still, the usual chain-cleaning routine will not work. On many mid-drive systems this is normal: the cranks can freewheel backwards independently of the chainring. You need to move the chain forwards by hand, with the rear wheel safely off the ground, or clean it a section at a time.
Do not use motor assistance or walk mode to power the chain through a brush or rag. Keep the system switched off and follow the bike manufacturer’s battery-removal instructions before maintenance. For a non-removable battery, follow that model’s isolation procedure rather than dismantling the bike to reach it.
First, check whether this is normal for your bike
With the bike stationary and switched off, turn the cranks backwards gently. If the chain does not move but the bike otherwise pedals normally, check the motor or bike manual before assuming there is a fault. Park Tool’s e-bike tool guidance explains why some mid-drive bikes require forward pedalling for chain cleaning.
A chain that will not move when you pedal forwards, jams, or skips under load is a different problem. Stop and investigate that before cleaning. Do not force the cranks against resistance.
Option 1: lift the rear wheel and use a suitable chain cleaner
Use a stable repair stand rated for the bike’s weight and clamp only where the bike manufacturer permits. Remove a user-removable battery as directed; this also reduces the weight you need to lift. Keep the rear wheel clear of the floor and check that the bike cannot tip when you turn a crank.
Choose a cleaner whose instructions explicitly allow the chain to run forwards. For example, the Park Tool CM-5.3 has a reversible handle for this purpose. That compatibility should not be assumed for every enclosed cleaner.
Fit the tool to the lower chain run in the orientation specified by its manufacturer, add the recommended bicycle-compatible cleaner and turn a crank forwards slowly by hand. Keep fingers, loose sleeves and rags away from the chainring, cassette and jockey wheels. Stop immediately if the chain runs out of line or the tool catches.
Option 2: clean stationary sections with a brush
You do not need an enclosed cleaning machine. Apply a suitable drivetrain cleaner with a brush, following its dilution and dwell-time instructions. Work on a stationary section, put the brush down, move the chain to expose the next section, then stop it again before continuing.
If you cannot support the bike safely with the rear wheel raised, do not improvise an unstable lifting arrangement. Use an appropriate stand or ask a workshop for help. Our bike cleaning-brush guide explains the different brush shapes; keep oily drivetrain brushes separate from those used near brakes.
Rinse, dry and lubricate
Remove the cleaner as instructed, wipe the chain and allow it to dry before lubricating. Keep degreaser and lubricant away from disc rotors and pads. Park Tool’s chain-care instructions recommend relubricating after cleaning and wiping away excess lubricant.
Follow the lube manufacturer’s application and settling-time guidance. Our MTB chain-lube guide covers the choice for different riding conditions. If you use a waxed chain, follow that wax system’s maintenance process instead of automatically applying an oil-based lube.
Should you jam the crank to make backpedalling work?
Do not wedge a tool between the crank and chainring or use a makeshift tie to defeat the freewheel. The forward-pedalling method avoids that workaround. The aim is controlled manual movement with the electrical system inactive, not finding a way to make the motor do the job.