Over time, normal use will cause some items to loosen. This could result in skipping gears or erratic shifting because of a slightly stretched shifter cable. A quick adjustment can be made while riding the bike (or on a bike stand) by simply using the Fine Adjust Knob on your shifter (red arrow). For a quicker process, we recommend powering down the bike during adjustment.
While turning the crank or pedaling on a flat calm road, turn the knob 3 times to the front and shift up and down to test the result. If there is no change, repeat the process. If the shifting becomes more jumpy, the bike can be returned to the initial state by turning the knob back 3 turns at a time. This makes it easier to remember where you started the adjustment, as the process should be relatively quick. The video below shows the process being done while the bike is on a rack.
If this quick test doesn’t remedy the issue, it may be time for a tuneup.