The owner’s manual is the source

The manufacturer sets service intervals by distance or by time, whichever comes first. Riding in heat, dust, stop-and-go city traffic or with a passenger and luggage usually counts as “severe conditions”, and the intervals get shorter. The ranges below are common examples only.

Engine oil and filter

This is the most frequent service. On most modern bikes the interval is a few thousand kilometres or once a year, even if you rode very little, because oil ages while it sits. Use the oil type and viscosity in the manual. On bikes with a wet clutch, ordinary car oil can make the clutch slip.

Chain and sprockets

  • Clean and lubricate every few hundred kilometres, and always after riding in rain or off-road.
  • Check the slack against the value in the manual. Too loose or too tight both wear the drive.
  • Replace the chain and sprockets together: a new chain on worn sprockets wears out quickly.

Brakes

  • Pads: check the thickness through the caliper. Do not wait for metal-on-metal noise.
  • Brake fluid absorbs moisture over time, so it is changed by time (often about every two years), regardless of distance.
  • Discs: the minimum thickness is stamped on the disc itself.

Tyres

Replace them by tread depth and wear indicators, and also by age. An old tyre hardens and loses grip even when the tread looks fine. The production date is on the sidewall as a four-digit code (week and year).

Items by time and by distance

  • Air filter: check more often in dusty areas.
  • Coolant, spark plugs and valve clearances: by your model’s schedule.
  • Battery: check before winter and after long storage. A maintenance charger helps if the bike stands for weeks.
  • Steering and wheel bearings, and fork oil: long intervals, by the schedule.

How not to forget

The simplest method is to log every service the moment it is done: date, mileage and exactly what was replaced. With that record you see what is coming up, and you get a clean service history that adds value when you sell the bike.

This guide is general. Exact intervals, oil types and values come only from the owner’s manual for your model or from an authorised workshop.

Sources: Yamaha owner’s manuals, as an example. Links do not imply that these organisations endorse MotoCircleX.