The pannier's top hooks click shut, but the bottom of the bag swings inward toward the wheel. That means the upper lock and lower restraint are doing different jobs. Stop using the loaded bag until the lower hook or anchor can hold it against a suitable rack member through the bike's full stationary movement.
Confirm the Top Is Actually Locked
Park the bike, empty the bag, and close both upper hooks using the bag maker's instructions. Look at each latch instead of relying only on a click. If the upper interface lifts or opens, solve that fit first; a lower hook cannot compensate for an unlocked top.
Check that the rack itself is tight and undamaged. Movement in the rack, rather than the bag, belongs to a different repair.
Find a Usable Lower-Rail Contact
Locate the lower hook, rotating anchor, or rail specified for the exact pannier system. Identify a rack stay it can wrap around without resting on a weld, cable, brake component, fender support, or moving part.
The lower restraint should oppose the direction in which the bag swings. A hook that barely touches a stay at one angle may release as the bag settles. If no approved rack member lies within the adjustment range, the bag and rack are not compatible in that position.
Check both sides of the rack independently. A brake assembly, motor cable, or frame shape may leave a suitable contact point on one side but not the other, so do not mirror the adjustment by sight.
Adjust Only Within the Bag System
Use the manufacturer's diagram to rotate or slide the lower anchor and then tighten it by the specified method. Do not extend its reach with cord, tape, a zip tie, or a homemade bracket. Adding cargo to press the bag downward also does not create lateral restraint.
After adjustment, move the empty bag gently toward and away from the wheel. The top hooks should stay locked, the lower anchor should remain engaged, and no part should approach the tire, spokes, rotor, chain, or motor cable.
Check the Loaded Shape Before Riding
Add a light, evenly placed test load while the electric bike remains parked. Confirm that the bag does not sag into the wheel path and that the rack and bag stay within their own load limits. Do not use a road test to discover unresolved contact.
Move the crank and wheel slowly by hand only after all restraints are secure and hands are clear. Stop immediately if the bag, hook, loose strap, or cargo enters any moving path.
The electric bike accessories guide covers broader carrying choices. When the top is secure but the bottom still swings, change the lower-anchor position, bag position, or complete carrying system rather than treating the upper click as enough.
