Aprilia RS 660 / Extrema — OEM Fluid, Tire Pressure & Maintenance Specs
659cc Liquid-Cooled Parallel-Twin DOHC 8-Valve 270° Crank (RSV4-Derived · APRC 6-Axis IMU · 100 hp) · Source: Aprilia RS 660 Official Manual & Factory Oil Capacity Revision Service Bulletin (2.3 L)
According to the Aprilia RS 660 Official Manual & Factory Oil Capacity Revision Service Bulletin (2.3 L), the 2021–Present Aprilia RS 660 / Extrema (chassis ZD4KS000/KS/KSA66) requires 2 L (2.11 US qt) of SAE 10W-50 (JASO MA2, API SN Fully Synthetic (Castrol Power1 Racing 10W-50)) engine oil for a drain-only change and 2.3 L (2.43 US qt) with filter service (1A023538 / HF138). Standard solo cold tire pressure is 250 kPa / 2.50 bar / 36 PSI front (120/70 ZR17 M/C (58W)) and 280 kPa / 2.80 bar / 41 PSI rear (180/55 ZR17 M/C (73W)), paired with 2× NGK MR9DI-7 spark plug(s) and a YTZ10S / LiFePO4 (Extrema) battery.
Drain only: 2 L (2.11 US qt)
R 280 kPa (2.80 bar)
Est. Range: ~306 km (190 mi)
1. Engine Lubrication, Filter & Clutch Specifications
| Clutch Architecture | Wet Multi-Plate Manual Clutch NEVER use JASO MB |
|---|---|
| Recommended Viscosity & Grade | SAE 10W-50 · JASO MA2 · API SN Fully Synthetic (Castrol Power1 Racing 10W-50) |
| Oil Volume (Drain / With Filter / Overhaul) |
• Drain only: 2 L (2.11 US qt) • With filter/strainer: 2.3 L (2.43 US qt) • Complete dry overhaul: 2.7 L (2.85 US qt) |
| OEM Oil Filter Code & Type | 1A023538 / HF138 |
| Correct Oil Level Check Method | Hold upright on level ground; rest dipstick UNTHREADED on filler neck (do NOT screw in) |
| Oil Drain Bolt Torque | 30 N·m (22.1 lb-ft / 3.06 kgf·m) — Use fresh crush washer |
2. Cold Tire Pressures, Wheels, Ignition & Drivetrain
| Front / Rear OEM Tire Sizes | Front: 120/70 ZR17 M/C (58W) · Rear: 180/55 ZR17 M/C (73W) (Tubeless) |
|---|---|
| Cold Tire Pressure — Solo Riding |
Front: 250 kPa / 2.50 bar / 36 PSI Rear: 280 kPa / 2.80 bar / 41 PSI |
| Cold Tire Pressure — 2-Up / Loaded Touring |
Front: 250 kPa / 2.50 bar / 36 PSI Rear: 280 kPa / 2.80 bar / 41 PSI |
| OEM Spark Plug & Quantity | NGK MR9DI-7 × 2 (Gap: 0.7–0.8 mm) |
| OEM Battery Code & Rating | YTZ10S / LiFePO4 (Extrema) (12V 8.6Ah AGM (Std) or LiFePO4 Lithium (Extrema)) |
| Final Drive Maintenance | 520 O-Ring Sealed Chain (17T/43T, 110 links) — Maintain ~30 mm slack |
| Brake Fluid & Coolant | DOT 4 · OAT Silicate-Free Coolant CUNA NC 956-16 (~1.8 L) |
3. Ergonomics, Range & Scheduled Service Intervals
| Displacement · Max Power · Peak Torque | 659 cc · 100 hp @ 10,500 rpm · 67 N·m (49.4 lb-ft) @ 8,500 rpm |
|---|---|
| Seat Height & Wet Curb Weight | 820 mm (32.3 in) · 183 kg (403 lbs) |
| Fuel Tank & Est. Real-World Range | 15 L (4.0 US gal) · ~20.4 km/L → ~306 km (190 mi) |
| OEM Scheduled Maintenance Intervals |
• First Break-In: 1,000 km • Engine Oil / Filter: 10,000 km / 10,000 km • Air Filter / Spark Plug: 20,000 km / 20,000 km • Valve Clearance Check: 20,000 km |
4. Generation Cutoffs & Real-World Wrenching Gotchas
Model-Year & Chassis Generation Notes
Revolutionizing middleweight twins in 2021 (verify early-2021 connecting-rod recall completion on used early VINs), the RS 660 added the lightweight SC-Project/lithium Extrema edition in 2023 and shares 100% of its engine consumables with the Tuono 660.
Oil & Clutch Mechanical Engineering Note
Crucial Aprilia factory revision: early print manuals listed 2.7 L (dry capacity), causing widespread overfilling until Aprilia revised the official filter-change refill down to 2.30 L (2.43 US qt) of SAE 10W-50 JASO MA2! Also note: check oil HOT after a 15 km ride with the bike upright and the dipstick resting UNTHREADED on the threads (do NOT screw it in).
Garage Wrenching Gotchas
- The stock black plastic dipstick is notoriously hard to read with clean golden synthetic oil—lay the tip sideways against a clean white paper towel right after pulling it, or upgrade to a silver CNC billet dipstick.
- At a lofty 13.5:1 compression ratio spinning to 11,500 rpm redline, check the 2.3 L sump every 1,000–1,500 km and feed it premium high-octane unleaded fuel.
5. Frequently Asked Questions (FAQ)
Does the Aprilia RS 660 take 2.3 L or 2.7 L of oil on an oil change?
2.30 L (2.43 US qt)! 2.7 L is the completely dry engine rebuild volume; Aprilia updated workshop manuals to 2.30 L with a new 1A023538 / HF138 filter to prevent airbox blow-by.
Do you screw the dipstick in to check oil on an Aprilia RS 660?
Do NOT screw it in! Per Aprilia’s RS 660 manual, ride ~15 km to full oil operating temperature, shut off on level ground, hold the bike vertical on both wheels, and insert the clean dipstick without tightening.
Can the RS 660 switch to GP reverse shift pattern without aftermarket parts?
Yes—Aprilia designed the 660 quickshifter linkage and APRC electronics to support street or GP reverse shift patterns cleanly.