How to Adjust a Shimano MTB Shifter

Mountain bikes take a real beating. Sometimes this results in bad shifting. It's almost always because of slack in the cables. Shimano equipped mountain bikes are easy to work on. They have built-in barrel adjusters for tightening cables. There is a barrel adjuster on the handlebar shifter that can be adjusted while riding the bike. This is usually all it takes to get your bike shifting like new.

Instructions

    • 1

      Go to an open area or parking lot. Begin riding your bike. Shift the bike into the smallest gear on the back and the middle gear on the front.

    • 2

      Push the lever to shift your bike up to the next biggest gear in back as you continue to pedal your bike. You should be able to feel the bike shift into the next-biggest gear.

    • 3

      Listen to the chain as you continue to pedal and ride slowly. If the bike does not shift at all or the bike shifts but the chain chatters, take your right hand off the grip and turn the barrel adjuster two turns counterclockwise. Continue to ride. The barrel adjuster is the black serrated knob that is attached to the shifter mechanism. It has a hole in it. The shifter cable passed directly through the center of the barrel adjuster.

    • 4

      Push the shifter lever to shift the bike to the next-biggest gear. Listen to the chain. If the bike chain is noisy or still will not shift, turn the barrel adjuster two more turns counterclockwise until the bike shifts. Continue to pedal the bike and ride slowly.

    • 5

      Shift the bike up one gear at a time to the biggest gear on the back as you ride. Listen for chain noise. If the bike shifts cleanly through to the biggest gear on the back, stop turning the barrel adjuster.

    • 6

      Push the button on the shifter one click at a time to shift the bike back down to the smallest gear. The bike should shift cleanly and without noise back down through all the gears. If it makes noise the cable may be too tight. Turn the barrel connector one click clockwise. Continue riding. Click the button again to shift the bike to the next smaller gear. Listen for noise. Turn the barrel adjuster one click clockwise until the bike shifts back down with no noise.