Want to eliminate sloppy, slow or imprecise shifting permanently? All it takes is a little practice to master setting your derailleur. Follow these easy steps to ensure quick and precise shifting.
Written by: Ian Buchanan
Step 1: Set The H Stop
The high “H” stop controls how far the derailleur can travel away from the wheel. With the cable unhooked, the chain should rest on the smallest gear.
1. Set the bike in a work stand or a trainer so you can pedal and shift while working.
2. Make sure the rear shift lever is set to the hardest gear, unhook the cable from the derailleur and screw the barrel adjuster all the way into the derailleur.
3. Pedal the bike. If the chain tries to jump into the second cog, turn the H stop screw counterclockwise in quarter-turn increments until it no longer skips. If the chain tries to jump off the smallest cog toward the frame, turn the H stop screw clockwise in quarter-turn increments until it turns smoothly.
4. Check the adjustment by pushing the derailleur up the cassette with your hand while turning the crank, then releasing the derailleur so it snaps back against the H stop screw. The chain should return to the smallest cog without over-shifting past the cassette.
Step 2: Set The L Stop
The low “L” stop controls how far the derailleur can move toward the wheel. It should be adjusted so the chain smoothly shifts to the biggest cog without nearing the spokes.
1. While rotating the crank slowly, push the derailleur toward the wheel with your hand to shift the chain into the biggest cog.
2. If you can push the derailleur so far that it tings against the spokes, turn the L stop screw clockwise until it no longer allows for this. The chain must still be able to rest on the largest cog.
3. Release the derailleur. Pull the cable taut with your hand and reattach it to the derailleur. Shift into the biggest cog. The chain should go into the easiest gear without over-shifting into the wheel or skipping.
Once the stops are adjusted, they should not need to be adjusted again, and cable tension will determine shift quality, which may need periodic adjustment.
Step 3: Adjust The Derailleur Cable Tension
Cable tension adjustment follows a simple rule: Turn the barrel adjuster in the direction the chain is not shifting smoothly.
1. With the drivetrain in the big chainring/small cog gear combination, turn the crank and shift into the second cog. If the chain hesitates, turn the barrel adjuster counterclockwise until the shifting improves. If the chain tries to over-shift or skip to the third cog, turn the barrel adjuster clockwise until the chain moves crisply onto the second cog with a single shift.
2. Test shift through all the gears and adjust cable tension until the chain shifts smoothly through every one.
In addition to maladjustment, these three problems can create sloppy shifting.
Component wear: Not only do chains wear out, but so do cassettes, chainrings and even shifters.
Dirty housing: Dirt and grease can get into the housing and prevent the cable from sliding freely. Swap your cables and housing yearly so they stay uninhibited.
Bent derailleur hanger: Rear derailleurs are mounted to bikes on a thin extension from the frame called a derailleur hanger. This piece can be bent, which ruins shifting. Bike shops have tools that can check and correct alignment.
Ian Buchanan is co-owner of Fit Werx (Fitwerx.com), with locations in Vermont and Massachusetts.