Harley-Davidson · Harley-Davidson Evolution Sportster (1986-2021)

Softail (Milwaukee-Eight)

Library entry covers 2018-2026

16 factory 32 guideline

Published source

2018 Maintenance Schedules (H-D factory, Touring Table 2-1, Softail Table 3-1)

Factory workshop manual. Covers 2018.

Open the source

48 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: Dry sump (separate oil tank)
Oil filtration: Replaceable cartridge or spin-on filter
Valve gear: Hydraulic lifters (no routine clearance adjustment)
Ignition: Electronic (CDI / transistor / ECU)
Charging: Alternator / stator with rectifier
Battery: Wet cell (flooded lead-acid, needs topping up)
Fuel system: Fuel injection
Cooling: Air / oil cooled
Primary drive: Chain in oil-bath case with its own oil
Gearbox oil: Separate gearbox oil
Clutch control: Hand lever, hydraulic
Final drive: Toothed belt
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 Harley-Davidson Softail (Milwaukee-Eight)

On the road: every 200 mi

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 300 mi

2 items

Check lights, horn, brake light switches

Pre-ride / on the road

Guideline
Check tire pressures

Pre-ride / on the road

Guideline

Every 3,000 mi or 12 months

5 items

Check throttle cable(s) free play and return

Fuel and air

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
Check wheel bearings for play

Wheels and tires

Guideline

Every 4,000 mi or 12 months

1 item

Inspect, clean and gap spark plugs

Engine

Guideline

Every 5,000 mi or 12 months

1 item

Inspect tire tread, sidewalls and date codes

Wheels and tires

Factory

Manual: Check tire pressure and inspect tread. Factory: every interval or annually, whichever first

Every 5,000 mi

8 items

Change engine oil

Engine

Factory

Manual: Replace engine oil and filter. Factory: marked at every column: 1000 mi then every 5000 to 50,000
Inspect exhaust system for leaks, cracks, loose fasteners

Engine

Factory

Factory: every interval
Replace oil filter

Engine

Factory

Manual: Replace engine oil and filter. Factory: with oil, 1000 then every 5000
Adjust clutch free play, lubricate cable and lever pivot

Primary and gearbox

Factory

Manual: Check clutch adjustment. Factory: every interval
Inspect drive belt, pulleys and tension

Final drive

Factory

Manual: Inspect drive belt and sprockets. Factory: every interval
Grease and check center / side stand and springs

Rear suspension and frame

Factory

Manual: Inspect and lubricate jiffy stand. Factory: every interval
Check brake pads and discs

Brakes

Factory

Manual: Inspect brake pads and discs for wear. Factory: every interval
Lubricate control cables and lever pivots

Controls and cables

Factory

Manual: Check, adjust, lubricate brake and clutch controls. Factory: every interval

Every 6,000 mi or 12 months

5 items

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 speedometer / tachometer cables, check drive

Controls and cables

Guideline

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

Every 10,000 mi or 12 months

1 item

Change primary chaincase oil

Primary and gearbox

Guideline

Every 10,000 mi or 2 years

2 items

Compression test (or leak-down)

Engine

Guideline
Check / adjust primary chain

Primary and gearbox

Guideline

Every 12,000 mi 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 15,000 mi 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 15,000 mi

1 item

Check spoke tension and wheel true

Wheels and tires

Factory

Manual: Check spoke tension. Factory: at 1000, 5000, 20,000, then every 15,000 mi

Every 20,000 mi or 4 years

1 item

Repack / replace wheel bearings

Wheels and tires

Guideline

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

Every 25,000 mi or 6 years

1 item

Replace swingarm bushes / bearings

Rear suspension and frame

Guideline

Every 30,000 mi or 2 years

1 item

Replace spark plugs

Engine

Factory

Factory: every 30,000 mi or two years, whichever first

Every 30,000 mi

1 item

Repack / replace steering head bearings

Front end

Factory

Manual: Lubricate steering head bearings, disassemble and inspect. Factory: footnote: every 30,000 mi

Every 50,000 mi

2 items

Replace drive belt (wear or damage based)

Final drive

Guideline
Rebuild forks: seals, bushes, springs

Front end

Factory

Manual: Front forks: disassemble, rebuild, replace oil. Factory: every 50,000 mi

Every 100,000 mi

1 item

Replace fuel filter

Fuel and air

Factory

Factory: every 100,000 mi

Every 12 months

1 item

Clean battery terminals, check charge and strap

Ignition and electrics

Factory

Manual: Check battery, terminal torque, clean connections. Factory: annually

Every 2 years

4 items

Inspect wiring, bullet connectors and ground points

Ignition and electrics

Guideline
Replace hydraulic clutch fluid

Primary and gearbox

Guideline
Inspect frame, welds and lugs for cracks

Rear suspension and frame

Guideline
Replace brake fluid

Brakes

Factory

Manual: Flush and replace DOT 4 brake fluid. Factory: every two years, sooner if moisture 3% or more

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.