How to adjust your MTB rear derailleur?

Are your rear gears unstable or have you just fitted your new derailleur? It is time to adjust it! Here is a video to help you carry out this operation on your mountain bike, which requires a little precision.

Time: 20 min
Level: Intermediate
Tools: Allen key set | Flat-nose pliers | Phillips screwdriver

Steps

Place the chain on the smallest sprocket, then release the derailleur cable.
Adjust the low limit screw (High) so that the alignment a is perfect between the derailleur jockey wheel and the outer surface of the smallest sprocket.
Operate the derailleur by hand to adjust the high limit screw (Low) of the derailleur so as to align it with the largest sprocket.
Fully screw in the barrel adjuster at the shifter, then unscrew it by 2 turns.
Refit the derailleur cable in its housing, pulling it slightly taut with the flat-nose pliers.
Place the drivetrain on the smallest chainring and the largest sprocket.
Adjust the B-tension screw so as to achieve the distance between the sprocket and the derailleur jockey wheel recommended by the manufacturer (generally 5 or 6 mm).
Run through all the gears to check that shifting occurs smoothly.
Complete the adjustment with the barrel adjuster at the shifter until you achieve the best possible smoothness of gear changes.
Probikeshop tip: to make the final adjustment easier, lubricate your MTB drivetrain.