Derailleurs are pretty much the unsung heroes of our bicycle. A great bike ride depends on how smooth-sailing it is and that mainly attributes to how well-adjusted your derailleurs are.
To know the optimal adjustments towards a good bike ride, here’s a how-to guide to adjust derailleurs.
Adjusting the front derailleur
Step 1: Set the gear lever to its lowest. Afterwards, undo the cable-securing bolt on the operating lever of the derailleur and move the cable out of the way.
Step 2: If there is no gap of approximately 2mm between the top of the largest chain wheel and the bottom of the outer plate of the derailleur, loosen the fixing clamp and realign it.
The front derailleur must be parallel to the chainring.
Step 3: Adjust the inner adjusting crew so that when the chain is on the smallest chainring, it sits in the middle of the side plates.
Step 4: With the chain on the smallest cog on the rear cassette, pedal the bike with one hand and pull the front derailleur so that the chain goes onto the largest chainring at the front.
Do so by screwing the outer adjusting screw on the derailleur body.
Step 5: Let the derailleur return to its position over the smallest chainring.
Then refit the cable and tighten the securing bolt.
Step 6: Test the front derailleur by moving the chain between the smallest and next chainring using the gear lever.
Crank the gear at 12 o’clock, 3 o’clock, 6 o’clock and 9 o’clock so the slight bend becomes more obvious. If the chain falls off the smaller chainring, adjust the inner derailleur accordingly.
Step 7: Put the chain onto the smallest cog on the rear cassette.
If the chain falls off the front of the chainring, adjust the outer derailleur adjusting screw, so the derailleur does not move quite so far out.
Step 8: Unscrew the cable adjuster on the gear lever if the derailleur is slowly changing up from small to big chainring.
Ensure that it doesn’t slow when changing down. Make sure that all the securing bolts are tight and go for a quick test ride.
Adjusting the rear derailleur:
Step 1: Shift the lever into top gear. Then turn the pedals and allow the chain to go onto the smallest cog on the cassette.
Step 2: Unscrew the cable-securing bolt and move the cable out of the way.
Step 3: Turn the pedals while using your other hand to push the derailleur towards the rear wheel.
If the derailleur’s inner adjusting screw is correctly adjusted, the chain will only travel onto the largest cog and go no further.
Step 4: If it goes beyond that cog and falls into the spokes, turn the derailleur clockwise and repeat step three.
If the chain does not sit comfortably on the biggest cog, unscrew it a little and try again.
Step 5: Let the derailleur’s spring to push the derailleur outwards onto the smallest cog.
If the chain does not fit properly on the smallest cog, turn the other screw to move the derailleur’s position.
Step 6: If it travels comfortably between the cogs on the cassette, refit the gear cable and do up the securing bolt.
Step 7: Using the gear lever, go through all the gears several times.
If the derailleur is slow in the lower gears, unscrew the cable adjuster on the derailleur body. If it is slow in the higher gears, screw in the cable adjuster.
Re-check that all the securing bolts are tight and go for a quick test ride.