If the chain looks and sounds right then it's usually following the correct path on the rear derailleur. If you're uncertain about this, look carefully at the old chain's route before you take it off, take pictures or make a sketch.
Set The Gear on the front and rear derailleur
If the rear derailleur has a cable connected select the highest gear. If the front derailleur has a cable connected select the lowest gear.
Use The Small End
If one end of the chain has a pin sticking out, thread the other end through the system.
Insert The ‘C’ Hook
Hang the ‘C’ hook near the end of the chain so it can’t pass through the rear derailleur.
Don’t let the chain drag on the floor. It will pick up dirt.
Dodge The Tab
There may be a metal tab between the plates of the cage that holds the two jockey wheels, make sure the chain passes this without rubbing on it.
Top Jockey Wheel
Pass the chain up around the front of the top jockey wheel on the rear derailleur.
Pass the chain through the front derailleur cage and engage it on the small cog at the front.
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