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Aprilia · Shim-adjusted overhead-cam four-stroke, wet sump, gearbox shares engine oil, chain drive

Tuono 660

Library entry covers 2020-2025

29 factory 50 guideline

Published source

Aprilia Tuono 660 use and maintenance book (Ed. 01_01/2021), ManualsLib

Factory owner's handbook. Covers edition Ed. 01_01/2021.

79 items for a 2021 model, grouped by interval the way a factory chart is laid out.

How this bike is built (what the schedule is based on)

Engine cycle: Four-stroke
Engine lubrication: Wet sump (oil in crankcase)
Oil filtration: Replaceable cartridge or spin-on filter
Valve gear: Overhead cam, shim adjusted (incl. desmo)
Ignition: Electronic (CDI / transistor / ECU)
Charging: Alternator / stator with rectifier
Battery: Wet cell (flooded lead-acid, needs topping up)
Fuel system: Fuel injection
Cooling: Liquid cooled
Primary drive: Gear or chain inside engine, shares engine oil
Gearbox oil: Shares engine oil
Clutch control: Hand lever, cable
Final drive: Chain
Front suspension: Telescopic fork
Rear suspension: Swingarm, single shock / cantilever
Front brake: Disc, hydraulic
Rear brake: Disc, hydraulic
Wheels: Cast / alloy, tubeless
Sidecar: No sidecar

Maintenance schedule

2021 Aprilia Tuono 660

On the road: every 300 km

1 item

Check engine oil level

Pre-ride / on the road

Guideline

Each fuel stop on old machines. Dry sump: check the tank hot, engine idling or just stopped, per your manual.

On the road: every 500 km

3 items

Check lights, horn, brake light switches

Pre-ride / on the road

Guideline
Check tire pressures

Pre-ride / on the road

Guideline
Lubricate drive chain

Pre-ride / on the road

Guideline

Lube warm, ideally at the end of the riding day so it soaks in overnight. Sooner after rain.

On the road: every 800 km

1 item

Check coolant level

Pre-ride / on the road

Guideline

On the road: every 1,000 km

1 item

Check chain slack and rear wheel alignment

Pre-ride / on the road

Guideline

Every 1,600 km or 6 months

1 item

Inspect tire tread, sidewalls and date codes

Wheels and tires

Guideline

Every 5,000 km or 12 months

9 items

Check throttle cable(s) free play and return

Fuel and air

Guideline
Clean drive chain thoroughly (remove and soak, re-lube)

Final drive

Guideline

Non O-ring chains on old machines: remove, clean, soak in hot chain grease or lube, refit with the master link clip closed end leading.
Inspect chain and sprockets for wear (measure stretch)

Final drive

Guideline
Check steering head bearing adjustment

Front end

Guideline
Inspect fork seals, stanchions and fork boots

Front end

Guideline
Check footrests, pegs, rear brake and gear lever pivots

Rear suspension and frame

Guideline
Grease and check center / side stand and springs

Rear suspension and frame

Guideline
Check brake pads and discs

Brakes

Guideline
Check wheel bearings for play

Wheels and tires

Guideline

Every 6,500 km or 12 months

2 items

Inspect, clean and gap spark plugs

Engine

Guideline
Adjust clutch free play, lubricate cable and lever pivot

Primary and gearbox

Guideline

Every 8,000 km or 12 months

2 items

Change engine oil

Engine

Guideline

Pre-1970 machines: many owners run non-detergent or classic-spec oil with no filter, so short intervals matter. Dry sump: drain the tank and the crankcase/sump, flush the tank and clean the feed and return screens.
Replace oil filter

Engine

Guideline

Every 9,500 km or 12 months

7 items

Inspect coolant hoses and clamps

Engine

Guideline
Clean / inspect air filter

Fuel and air

Guideline

Mesh or oiled foam: clean and re-oil. Paper: blow out or replace. Some very early machines have no filter at all.
Check charging voltage and regulator / cut-out

Ignition and electrics

Guideline
Check swingarm bushes for play

Rear suspension and frame

Guideline
Inspect rear shocks for leaks and damping

Rear suspension and frame

Guideline
Lubricate control cables and lever pivots

Controls and cables

Guideline
Lubricate speedometer / tachometer cables, check drive

Controls and cables

Guideline

A dry speedo cable whips the needle and eventually kills the instrument.

Every 10,000 km or 12 months

14 items

Braking system (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Coolant (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Diagnostics

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Engine oil (replace)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Oil filter (replace)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Vehicle general operation (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Clutch cable (lubricate)

Primary and gearbox

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Side stand, stop light, clutch and throttle (inspect)

Primary and gearbox

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Drive chain (inspect and lubricate)

Final drive

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km and every 10000 km; inspect every 12 months. Check, clean, adjust or replace if necessary before every journey.
Steering bearings and steering clearance (inspect)

Front end

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Brake discs and brake pads (inspect)

Brakes

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months; check at each engine start.
Brake fluid (inspect)

Brakes

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.
Tires, pressure and wear (inspect)

Wheels and tires

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km and every 12 and 24 months; check at each engine start.
Wheel bearings and wheels (inspect)

Wheels and tires

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km or 12 months.

Every 10,000 km

6 items

Cooling system (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 10000 km.
Headlight aiming (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 10000 km.
Nut and bolt tightness (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km.
Vehicle set-up (inspect)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 1000 km, then every 10000 km.
Air filter (inspect)

Fuel and air

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 10000 and 30000 km.
Sprockets and chain tensioner (inspect)

Final drive

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 10000 km.

Every 16,000 km or 2 years

1 item

Compression test (or leak-down)

Engine

Guideline

Every 19,500 km or 2 years

4 items

Replace air filter element

Fuel and air

Guideline
Synchronize throttle bodies

Fuel and air

Guideline
Clean and grease rear suspension linkage

Rear suspension and frame

Guideline
Grease swingarm pivot

Rear suspension and frame

Guideline

Every 20,000 km or 12 months

2 items

Front suspension, fork (inspect)

Front end

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 20000 and 40000 km, and every 12 months.
Rear shock absorber (inspect)

Rear suspension and frame

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 20000 and 40000 km, and every 12 months.

Every 20,000 km

4 items

Spark plug (replace)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 20000 km.
Valve clearance (adjust)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 20000 km.
Air filter (replace)

Fuel and air

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 20000 km.
Fork oil seals (inspect)

Front end

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 20000 and 40000 km.

Every 24,000 km or 3 years

1 item

Change fork oil

Front end

Guideline

Some early telescopic forks are grease filled or use very small oil quantities. Check your manual.

Every 24,000 km or 4 years

1 item

Check valve clearances (shim adjusted)

Engine

Guideline

Every 25,500 km or 4 years

1 item

Replace spark plugs

Engine

Guideline

Every 29,000 km

1 item

Replace chain and sprockets (wear based)

Final drive

Guideline

Every 32,000 km or 4 years

2 items

Repack / replace steering head bearings

Front end

Guideline

Many old machines use loose balls in cups and cones. Taper roller conversions are common.
Repack / replace wheel bearings

Wheels and tires

Guideline

Cup-and-cone and taper roller hubs need periodic repacking and adjustment.

Every 38,500 km or 4 years

1 item

Replace fuel filter

Fuel and air

Guideline

Every 40,000 km or 4 years

1 item

Fork oil (replace)

Front end

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. At 40000 km or 4 years, whichever comes first.

Every 40,000 km or 6 years

1 item

Replace swingarm bushes / bearings

Rear suspension and frame

Guideline

Every 48,500 km or 6 years

1 item

Rebuild forks: seals, bushes, springs

Front end

Guideline

Every 6 months

1 item

Clean battery terminals, check charge and strap

Ignition and electrics

Guideline

Every 2 years

6 items

Coolant (replace)

Engine

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 24 months.
Replace coolant

Engine

Guideline
Inspect wiring, bullet connectors and ground points

Ignition and electrics

Guideline
Inspect frame, welds and lugs for cracks

Rear suspension and frame

Guideline
Brake fluid (replace)

Brakes

Factory

Factory: Scheduled maintenance table (Aprilia Tuono 660 use and maintenance book, Ed. 01_01/2021, English/Polish edition, printed p.188-190). Columns: 1000 km (0.6 mi x1000), 10000 km (6.2), 20000 km (12.4), 30000 km (18.6), 40000 km (24.9), every 12 months, every 24 months. Key: I inspect and clean, adjust, lubricate or replace if necessary; C clean; R replace; A adjust; L lubricate. Halve the intervals in rainy or dusty conditions, off road or for track use. Item names on p.189 are read from the Polish half of the chart where the English text layer is missing. Every 24 months.
Replace brake fluid

Brakes

Guideline

Every 4 years

3 items

Replace fuel lines

Fuel and air

Guideline

Old rubber and modern ethanol fuel do not mix well.
Inspect brake hoses; replace old rubber

Brakes

Guideline
Rebuild calipers and master cylinders (seals)

Brakes

Guideline

Every 6 years

1 item

Replace tires on age (regardless of tread)

Wheels and tires

Guideline

Guideline lines: Intervals here are general guidelines for the machine's era and layout, compiled for this app. They are not factory manual figures. Check your workshop manual, and edit any interval in the bike's Schedule tab.