Chain snaps or wears quickly, leading to skipped gears/drops
Replace with 9-speed compatible chain (for D50/ST50). Reference manual for chain length, or ask support for details.
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Fixing the Stax Chain Falling Off Issue
Step 1: Torque the Crankset to 35 Nm The first step in ensuring your chain remains secure is to properly tighten the crankset bolt. Using a torque wrench, tighten the bolt securing the crankset to a torque specification of 35 Newton-meters (Nm). Step ...
Chain comes off, misalignment
Set derailleur limits, check tension, verify chain-line as per manual. Escalate if unresolved. Use this tutorial to seat derailleur limits. https://www.youtube.com/watch?v=GWRdLIg79Mo
Difficult to change gears; noisy or skips
Adjust derailleur as per manual. Lubricate cables/chain; ensure hanger is straight.
Battery stops charging or discharges quickly
Try another charger. Test battery on different D50/ST50 if possible. If battery at fault and <1yr, contact ENVO for warranty.
The ebike is skipping gears
Derailleur not in optimal position for gear Adjust derailleur position with barrel adjuster located on the shifter