This is the maintenance schedule for the FLHR Road King with the Milwaukee-Eight motor made from 2017 onward, sourced from the owner’s manual. It replaces the earlier Twin Cam 103 Road King, most recently the High Power Twin Cam 103 Road King.
The Harley-Davidson Road King is the stripped down bagger in the Motor Company’s touring line.
It’s powered by the smaller of the Milwaukee-Eight motors, the 107 c.i. (1746 cc) air/oil-cooled V-twin with four valves per cylinder. H-D quotes peak torque of 111 lb-ft (150 Nm) at 3250 rpm. Final drive is via a 6-speed transmission and a belt.
Harley-Davidson also makes a higher-spec FLHRXS Road King Special with the higher-spec Milwaukee Eight 114 motor (since 2019), a different sized front wheel, no windshield, and a number of cosmetic differences.
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Harley-Davidson FLHR Road King (2017+) Service Intervals
Like most Harley-Davidson motorcycles, the Harley-Davidson FLHR Road King (2017, with the Milwaukee-Eight engine) has 5000 mile / 8000 km or annual service intervals.
At every service, change the oil and filter, and look over the motorcycle for items needing lubrication, adjustment, or cleaning. Also check wearable items (like hoses and tires) to see if they’re still in good condition.
As the Road King (and nearly every Harley-Davidson) has self-adjusting hydraulic valve lifters, there is no valve service interval. However, Harley-Davidson does suggest you change the spark plugs every 30000 miles / 48000 km or two years. Of course, if valves become noisy, then have a mechanic look at them, as some section of the system may have failed.
As well as engine oil, you need to periodically replace both primary chaincase lubricant and transmission lubricant.
A number of items need to be done less frequently, like changing the brake fluid. See the schedule for more details.
Harley-Davidson FLHR Road King (2017+) Maintenance Schedule
Below is the maintenance schedule for the FLHR Road King. The Road King has the standard Milwaukee-Eight 107 motor, not the larger capacity variant, nor the Twin-Cooled (liquid-cooled) version seen in some of the Ultra or CVO models.
Below is the maintenance schedule for the Harley-Davidson FLHR Road King.
- To keep the schedule more readable, we’ve cropped it at 30000 miles / 48000 km. Keep repeating it in the pattern shown.
- Follow the earlier of time-based or distance-based service intervals.
|mi x 1000||1||5||10||15||20||25||30|
|km x 1000||1.6||8||16||24||32||40||48||Every|
|Inspection checklist (see below) – Perform||✓||✓||✓||✓||✓||✓||✓||Year (some items only)|
|Engine oil – Replace||✓||✓||✓||✓||✓||✓||✓||Year|
See notes below
|Oil filter – Replace||✓||✓||✓||✓||✓||✓||✓||Year|
|Air cleaner filter – Inspect|
Clean as necessary in lukewarm water with mild detergent
|✓||✓||✓||✓||✓||✓||More often if riding in severe conditions.|
|Spark plugs – Replace||✓||2 years|
|(Spoked rims) Spoke tightness (front and rear) – Check||✓||✓||✓||More often if riding in severe conditions.|
|Hand control switch housing screw torque – Tighten||✓||✓||✓||✓||Year|
|Front brake handlebar clamp screw torque – Tighten||✓||✓||✓||✓||Year|
|Steering head bearings – Lubricate||✓|
|Windshield bushings – Inspect||✓||✓||✓|
|Primary chaincase lubricant – Replace||✓||✓||✓||✓||More often if riding in severe conditions.|
|Transmission lubricant – Replace||✓||✓||More often if riding in severe conditions.|
|Brake systems – Replace (use DOT 4 fluid)||2 years|
|(2017-2020 Hydraulic clutch models) Clutch fluid – Replace||2 years|
|Front and rear axle nut torque – Tighten||✓||✓||✓||✓||Year|
|12 battery – Check battery, terminal torque, and clean connections. Lubricate with electrical contact lubricant||Year|
|Fuel filter – Replace||100000 mi (161000 km)|
Standard Inspection Checklist
Below is the standard inspection checklist for the Road King (Milwaukee Eight). Do these items per the schedule above.
Not all items need to be checked annually — those that are are marked on the right.
Note that from 2017-2020, the Road King and other Tourers had a hydraulic clutch (The Road King didn’t get the Project Rushmore hydraulic clutch in the Twin Cam generation, unlike other Tourers). Harley-Davidson went back to a cable clutch from 2021.
|Standard Inspection Checklist — Milwaukee Eight||Annual|
|Drive belt and sprockets – Inspect|
|Drive belt – Check / Adjust tension|
|Rear sprocket isolators – Inspect at every tire change|
|Electrical equipment and switches – Inspect|
|Tire pressure and tread (front and rear) – Check||✓|
|Brake and clutch controls – Lubricate|
|Brake pads (front and rear) – Wear check|
Minimum thickness: 0.4 mm / 0.016 in
|Brake fluid level (front and rear) – Inspect level (fluid drops as pads wear), and check moisture content. Replace if moisture over 3%.|
|2017-2020: Clutch fluid level – Inspect level and check moisture content. Replace if moisture over 3%.||✓|
|2021+: Clutch cable – Adjust and check for leaks, contact, or abrasion. Lubricate cable with Harley-Davidson lubricant|
|Oil cooler – Clean|
|Oil and brake lines – Inspect|
|Jiffy stand – Lubricate|
|Exhaust system, fasteners, and shields – Inspect|
|Fuel door hinge and latch – Lubricate|
|Component and system function – Road test|
Wheel / Tire Size
The FLHR Road King ships with Dunlop bias blackwall tires, custom made for Harley-Davidson.
In 2020, Harley-Davidson changed the standard tire sizes for the base model FLHR Road King. See the two tables below.
2017-2019 Road King tire sizes:
|Wheel||Wheel size||Tire size||Tire pressure (cold)|
|Front||17 x 3 in||130/80B17 65H||36 psi / 248 kPa|
|Rear||16 x 5 in||180/65B16 81H||36 psi / 248 kPa|
2020+ Road King tire sizes:
|Wheel||Wheel size||Tire size||Tire pressure (cold)|
|Front||18 x 3.5 in||130/80B18 63H||36 psi / 248 kPa|
|Rear||18 x 5 in||180/55B18 80H||40 psi / 276 kPa|
Oil Change on the FLHR Road King
There are three fluids that need to be changed on the Road King.
For all of them, you can use Castrol V-Twin 20W50, a popular oil for Harley-Davidson motorcycles.
- Engine oil (See below table)
- Primary chaincase lubricant (1L of Formula+ Transmission and Primary Chaincase Lubricant OR Screamin’ Eagle Syn3 Synthetic 20W50)
- Transmission lubricant (1L of Formula+ Transmission and Primary Chaincase Lubricant OR Screamin’ Eagle Syn3 Synthetic 20W50)
For engine oil, use any of the following oils. Generally one of the first two is appropriate for most people.
|Lowest ambient temperature||Oil brand||Weight|
|30 F / -1 C||Screamin’ Eagle SYN3 Synthetic||SAE 20W50|
|40 F / 4 C||Harley-Davidson H-D 360||SAE 20W50|
|60 F / 16 C||Harley-Davidson H-D 360||SAE 50|
|80 F / 27 C||Harley-Davidson H-D 360||SAE 60|
While the standard oil change interval is 5000 miles / 8000 km, H-D recommend you change the oil every 1500 mi / 2400 km if you frequently ride the motorcycle short distances (less than 15 mi / 24 km) in ambient temperatures below 60 degrees F / 16 C. For example, if you’re regularly riding in winter in most of the northern hemisphere, you’ll want to change the oil more often.
Belt Tension Check / Adjustment
To check the belt tension on your FLHR Road King, follow the procedure below.
You need a belt tension tool and a ruler.
- Put the motorcycle in neutral on its stand, with the rear wheel on the ground, and nothing in the saddlebags.
- Push up on the middle of the bottom half of the belt until the belt tension gauge registers 10 lb (4.5 kg) of pressure.
- Use the ruler to measure belt tension
Target belt tension for the FLHR Road King: 3/18-9/16 in / 9.5-14.3 mm
If the belt tension is out of spec, you can either adjust it yourself if you’re familiar with how, or take it to a dealer.
About the 2017+ Harley-Davidson FLHR Road King
The Harley-Davidson FLHR Road King has been a mainstay of Harley-Davidson’s line-up since the 90’s. It’s part of the touring line, and is designed for long-distance travel — in style.
The FLHR Road King is a stripped-back bagger. It doesn’t have a fairing or a rear seat, but it does have bags and a windshield. The core of the Road King is the base 107 c.i. Milwaukee-Eight motor that has been the core engine in the Harley-Davidson line-up since 2017 when it was introduced, replacing the Twin Cam motor of the last generation.
As a premium motorcycle, you might wonder how anyone can call the Road King “stripped back”. How exactly is anything named “king” a modest motorcycle? Well, it becomes more apparent when you compare the Road King with its higher-end stablemates. It doesn’t have a TFT display, it doesn’t have a sound system, and doesn’t have a rear seat for a passenger. Even the fairing is just a windshield, as iconic as it is. The Road King has everything you need for a trip, and nothing more.
The Milwaukee-Eight motor deserves special mention. It’s a long-awaited update to the Twin Cam motor, and brings with it a few welcome improvements that has almost universal praise from the Harley-Davidson riding community. It has all the character of the earlier motor but without the crazy shakiness (thanks to a counter-balancer shaft), and is tuned to be able to make power all the way through the rev range, making for a very rewarding ride.
Riding any motorcycle with the new M8 motor is very rewarding. There’s a big rumble down low, as you’d expect, and a huge wave of torque that is rewarding to rev to 5000 rpm without needing to short-shift as aggressively. As always, there’s passing power in abundance without having to downshift.
The front brakes on the Road King sound impressive — Brembo calipers on twin 300 mm rotors. But these aren’t the same Brembos you’ll find on sport bikes. They work well, but you do need to put effort into them. ABS is optional in the US, though standard in others, and always comes with linked brakes.
Harley-Davidson improved the suspension on their Touring range for 2017 onward. It’s still a Showa dual bending valve unit, but it’s of an improved design that responds much better than the old version, reacting well to big bumps without bottoming out as easily. The new suspension also comes with a remote preload adjuster on the left hand side.
You might also recognise the FLHR as a police motorcycle. It’s a popular choice as a police bike in the USA, ideal as it’s comfortable for all-day riding.
Harley-Davidson also makes the FLHRXS Road King Special, which from 2019 has had a Milwaukee-Eight 114 motor, and has a larger front tire, and slightly different maintenance specs.
Reference — Manual for the Harley-Davidson FLHR Road King (2017+)
The above information came mainly from the maintenance section of the Harley-Davidson Touring manual, with specific adaptations for the Road King (for example, omitting the section about “coolant” — the Road King isn’t liquid-cooled).
You can see the manual for yourself online here (subscription required).