Shifts not smooth, skips gear, chain falls off
Inspect derailleur hanger for bends (see #1), re-adjust limits/tension, confirm cable routing.
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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 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.Difficult to change gears; noisy or skips
Adjust derailleur as per manual. Lubricate cables/chain; ensure hanger is straight.Flex Trike Chain rubbing on low gear
1: Unfasten these bolts. 2: Slide the freewheel assembly shown in the direction of arrow. 3: Fasten the boltsChain 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