Harley-Davidson CVO Road Glide ST 121 HO (FLTRXSTSE) — OEM Fluid, Tire Pressure & Maintenance Specs
1,977cc Liquid-Cooled Head High-Lift Cam Milwaukee-Eight 121 High Output · Source: Harley-Davidson CVO Road Glide ST 121 HO (FLTRXSTSE) (2024–Present) Official Owner’s Manual Maintenance Specifications
According to the Harley-Davidson CVO Road Glide ST 121 HO (FLTRXSTSE) (2024–Present) Official Owner’s Manual Maintenance Specifications, the 2024–Present Harley-Davidson CVO Road Glide ST 121 HO (FLTRXSTSE) (chassis FLTRXSTSE) requires 4.3 L (4.54 US qt) of SAE 20W-50 (JASO MA2, Screamin’ Eagle SYN3 20W-50 / H-D 360 20W-50) engine oil for a drain-only change and 4.7 L (4.97 US qt) with filter service (HD 62700296 / 62700297 (HF171C)). Standard solo cold tire pressure is 248 kPa / 2.48 bar / 36 PSI front (130/60B19 M/C 61H) and 276 kPa / 2.76 bar / 40 PSI rear (180/55B18 M/C 80H), paired with 4× HD 6R10 (31600012 Dual-Plug M8) spark plug(s) and a HD Lithium LiFePO4 / YIX30L-BS battery.
Drain only: 4.3 L (4.54 US qt)
R 276 kPa (2.76 bar)
Est. Range: ~363 km (226 mi)
1. Engine Lubrication, Filter & Clutch Specifications
| Clutch Architecture | Wet Multi-Plate Manual Clutch NEVER use JASO MB |
|---|---|
| Recommended Viscosity & Grade | SAE 20W-50 · JASO MA2 · Screamin’ Eagle SYN3 20W-50 / H-D 360 20W-50 |
| Oil Volume (Drain / With Filter / Overhaul) |
• Drain only: 4.3 L (4.54 US qt) • With filter/strainer: 4.7 L (4.97 US qt) • Complete dry overhaul: 5.2 L (5.49 US qt) |
| OEM Oil Filter Code & Type | HD 62700296 / 62700297 (HF171C) |
| Correct Oil Level Check Method | At full operating temperature resting ON THE SIDESTAND (Jiffy Stand); thread dipstick in to read |
| Oil Drain Bolt Torque | 24 N·m (17.7 lb-ft / 2.45 kgf·m) — Use fresh crush washer |
| Primary Chaincase Fluid | 1065 ml (1.06 L) — H-D Formula+ Primary & Clutch Fluid (900–1,065 ml wet refill) |
| Separate Transmission / Gearbox Oil | 828 ml (0.83 L) — H-D Formula+ or Heavy Synthetic Gear Oil 80W-140 (828 ml / 28 oz) |
2. Cold Tire Pressures, Wheels, Ignition & Drivetrain
| Front / Rear OEM Tire Sizes | Front: 130/60B19 M/C 61H · Rear: 180/55B18 M/C 80H (Tubeless) |
|---|---|
| Cold Tire Pressure — Solo Riding |
Front: 248 kPa / 2.48 bar / 36 PSI Rear: 276 kPa / 2.76 bar / 40 PSI |
| Cold Tire Pressure — 2-Up / Loaded Touring |
Front: 248 kPa / 2.48 bar / 36 PSI Rear: 276 kPa / 2.76 bar / 40 PSI |
| OEM Spark Plug & Quantity | HD 6R10 (31600012 Dual-Plug M8) × 4 (Gap: 0.8–0.9 mm) |
| OEM Battery Code & Rating | HD Lithium LiFePO4 / YIX30L-BS (12V Heavy-Duty LiFePO4 / AGM) |
| Final Drive Maintenance | Carbon/Aramid Reinforced Secondary Belt — Inspect belt deflection and pulley debris |
| Brake Fluid & Coolant | DOT 4 · Harley-Davidson Extended Life OAT Coolant (121 High Output Heads) |
3. Ergonomics, Range & Scheduled Service Intervals
| Displacement · Max Power · Peak Torque | 1977 cc · 127 hp @ 4,900 rpm · 193 N·m (142.3 lb-ft) @ 4,000 rpm |
|---|---|
| Seat Height & Wet Curb Weight | 720 mm (28.3 in) · 380 kg (838 lbs) |
| Fuel Tank & Est. Real-World Range | 22.7 L (6.0 US gal) · ~16 km/L → ~363 km (226 mi) |
| OEM Scheduled Maintenance Intervals |
• First Break-In: 1,600 km • Engine Oil / Filter: 8,000 km / 8,000 km • Air Filter / Spark Plug: 24,000 km / 48,000 km • Valve Clearance Check: 48,000 km |
4. Generation Cutoffs & Real-World Wrenching Gotchas
Model-Year & Chassis Generation Notes
Introduced in 2024 as the most powerful factory bagger built, the FLTRXSTSE drops VVT for a high-lift cam and 5,900 rpm redline in the 127 hp M8 121 HO, forged carbon bodywork, and titanium mufflers.
Oil & Clutch Mechanical Engineering Note
Spinning to 5,900 rpm with 193 Nm of torque and a high-lift fixed cam, hard Track-mode riding warrants shortening SYN3 20W-50 engine and 80W-140 gearbox intervals to 5,000–6,000 km.
Garage Wrenching Gotchas
- When equipped with the factory lightweight LiFePO4 battery, never attach a lead-acid charger running high-voltage desulfation pulses; use a lithium-compatible smart tender only.
- Wash forged-carbon fenders and anodized Showa remote-reservoir shock bodies with pH-neutral soap rather than harsh alkaline degreasers that cloud clearcoats and anodizing.
5. Frequently Asked Questions (FAQ)
How are engine and separate drivetrain fluid capacities split on the Harley-Davidson CVO Road Glide ST 121 HO (FLTRXSTSE)?
The engine sump takes 4.3 L drain-only and 4.7 L (4.97 US qt) with filter (HD 62700296 / 62700297 (HF171C)) of SAE 20W-50 (JASO MA2), while isolated drivetrain cavities (primary chaincase 1065 ml, separate gearbox 828 ml) require dedicated gear/chaincase fluid.
How do you accurately check the oil level on the CVO Road Glide ST 121 HO (FLTRXSTSE), and what are its service intervals?
Bring the engine to full operating temperature and check the Full Hot mark with the motorcycle resting on its sidestand (Jiffy Stand) on level pavement—measuring upright leads to crankcase overfill and breather blow-by. Torque the drain plug to 24 N·m with a new crush washer. Factory oil change intervals are every 8,000 km, with valve clearance inspection every 48,000 km.
What are the cold tire pressures, puncture repair type, seat height, and range of the CVO Road Glide ST 121 HO (FLTRXSTSE)?
Fitted with 130/60B19 M/C 61H front and 180/55B18 M/C 80H rear tubeless rims (compatible with roadside plug kits), set cold tire pressures to 36 / 40 PSI (248/276 kPa) solo or 36 / 40 PSI loaded. Seat height is 720 mm (28.3 in) at 380 kg wet weight, delivering ~363 km per 22.7 L tank.