KNOW WHEN YOU NEED A SERVICE
Your bicycle should be service every six months to a year depending on its use. The chain should also be cleaned and oiled regularly. The chain also needs to be checked for chain wear this can normally be done for free by most bike shops and could save you money on worn cassettes and sprockets. Below is a list of indicators you are in need of a service.
Gear change is slow
This will cause wear to your drive chain and derailleur.
as this can mean your pads are worn and will lead to damage to rim/disc
movement in the headset/handle bars
this will become more apparent when holding in the front brake and rocking the bicycle back and forth. If not fix can lead to damage to frame.
if you notice side to side movement when spinning the wheel your wheels may need to be re-trued. If left can cause damage to the wheels as well as interfere with braking
clicking noise when peddling
this my be a sign your bottom bracket needs replacing