Normally, proper adjustment is all that's needed to fix this issue. Please see this short video to learn how to adjust your 7-speed bicycle:
Here is a list of the steps to properly adjust your gears. These steps need to be followed in this exact sequence to achieve the best results.
1. Turn the handlebar shifter all the way to 7th gear. If possible, do this while turning the pedals. Otherwise, shift a couple of gears at a time, turning the pedals intermittently until the shifter is in 7th gear.
2. Loosen the 9mm pinch nut on the derailleur to detach the cable from the derailleur. This step is the most critical step in the process.
3. Turn the "h" or high limit screw so that the derailleur pulleys (the two little gear wheels) are aligned with the small cog. The derailleur should be positioning the chain as close as possible to the next smallest gear without rubbing.
4. When the derailleur is perfectly aligned with the smallest cog, reattach the cable to the derailleur by securing it with the 9mm pinch nut. It is important to try to take out as much slack from the cable as possible.
5. Now shift the handlebar shifter into 6th gear. Most likely, the chain will not shift into the next smallest cog. This normal because it is the cable usually has some slack in it. Please see the next step to for increasing tension on the cable.
6. If the derailleur is not moving the chain into 6th gear, turn the barrel adjuster counterclockwise a couple of turns. This will increase tension on the cable and pull the derailleur inward. Turn the barrel adjuster until the derailleur shifts perfectly between 6th and 7th. Test it back and forth a few times.
7. Now try shifting from 6th to 5th gear. If the movement is a little sluggish, you may want to give the barrel adjuster another half-turn or so.
8. At this point, you should have a perfectly adjusted derailleur. Shift slowly down to 1st gear, going at a slow pace to check shifting for each step on the way down to 1st gear.
9. Sometimes the derailleur will progress smoothly through all the gears but will not go into 1st gear. This is because the "L" or low limit screw is blocking the movement of the derailleur. Back the low limit screw out a couple of turns and see if this allows the derailleur to move all the way to shift the chain from 2nd to 1st gear.
10. Test ride the bike to check your adjustments. Shift up and down through the full range a few times. At this stage, fine-tuning can usually be achieved with the barrel adjuster. If you have trouble down-shifting into lower gears, then add more cable tension by turning the barrel adjuster counterclockwise. If there is a delay in dropping into higher gears, then let out a little slack by turning the barrel adjuster clockwise.
Please let us know if you need any additional assistance and we will either help you or get you in touch with one of our mechanics.
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