BMW R nineT / R 12 nineT (K21 / KR1) — OEM Fluid, Tire Pressure & Maintenance Specs
1,170cc Air/Oil-Cooled Flat-Twin DOHC Boxer (Dry Single-Plate Clutch + Separate Gearbox) · Source: BMW Motorrad R nineT (K21 / 0J01) & R 12 nineT Official Rider’s Manual
According to the BMW Motorrad R nineT (K21 / 0J01) & R 12 nineT Official Rider’s Manual, the 2014–Present BMW R nineT / R 12 nineT (K21 / KR1) (chassis K21 (R nineT)/K22/K23 (Pure/Scrambler)/KR1 (R 12 nineT)) requires 3.7 L (3.91 US qt) of SAE 15W-50 (JASO MA2, API SJ / JASO MA2 (BMW Advantec Pro 15W-50 — No Moly Additives)) engine oil for a drain-only change and 4 L (4.23 US qt) with filter service (11427673541 / 11425B79146 (Mahle OC 306 / HF164)). Standard solo cold tire pressure is 250 kPa / 2.50 bar / 36 PSI front (120/70ZR17 M/C (58W)) and 290 kPa / 2.90 bar / 42 PSI rear (180/55ZR17 M/C (73W)), paired with 4× NGK MAR8B-JDS (Twin-Spark DOHC Boxer) spark plug(s) and a YTX14-BS / BMW 12V 14Ah AGM battery.
Drain only: 3.7 L (3.91 US qt)
R 290 kPa (2.90 bar)
Est. Range: ~353 km (219 mi)
1. Engine Lubrication, Filter & Clutch Specifications
| Clutch Architecture | Dry Single-Plate Manual Clutch (Separate Gearbox Oil) |
|---|---|
| Recommended Viscosity & Grade | SAE 15W-50 · JASO MA2 · API SJ / JASO MA2 (BMW Advantec Pro 15W-50 — No Moly Additives) |
| Oil Volume (Drain / With Filter / Overhaul) |
• Drain only: 3.7 L (3.91 US qt) • With filter/strainer: 4 L (4.23 US qt) • Complete dry overhaul: 4.3 L (4.54 US qt) |
| OEM Oil Filter Code & Type | 11427673541 / 11425B79146 (Mahle OC 306 / HF164) |
| Correct Oil Level Check Method | Hold bike upright on level ground 3–5 min after warm shutdown; read crankcase sight glass |
| Oil Drain Bolt Torque | 32 N·m (23.6 lb-ft / 3.26 kgf·m) — Use fresh crush washer |
| Separate Transmission / Gearbox Oil | 800 ml (0.80 L) — SAE 75W-90 Synthetic Hypoid GL-5 (~700–800 ml until flush with lower filler threads) |
| Final Drive / Bevel Gear Oil | 180 ml (0.18 L) — Hypoid Axle Oil G3 SAE 75W-90 / 70W-80 (180 ml) |
2. Cold Tire Pressures, Wheels, Ignition & Drivetrain
| Front / Rear OEM Tire Sizes | Front: 120/70ZR17 M/C (58W) · Rear: 180/55ZR17 M/C (73W) (Tube-Type Spoke Rim) |
|---|---|
| Cold Tire Pressure — Solo Riding |
Front: 250 kPa / 2.50 bar / 36 PSI Rear: 290 kPa / 2.90 bar / 42 PSI |
| Cold Tire Pressure — 2-Up / Loaded Touring |
Front: 250 kPa / 2.50 bar / 36 PSI Rear: 290 kPa / 2.90 bar / 42 PSI |
| OEM Spark Plug & Quantity | NGK MAR8B-JDS (Twin-Spark DOHC Boxer) × 4 (Gap: 0.8 mm) |
| OEM Battery Code & Rating | YTX14-BS / BMW 12V 14Ah AGM (12V 14.0Ah MF AGM) |
| Final Drive Maintenance | Paralever Shaft Drive — Separate 6-speed gearbox (~800 ml) + rear bevel gear (180 ml) fluids |
| Brake Fluid & Coolant | DOT 4 · Air/Oil-Cooled Boxer Engine (No liquid coolant — front-mounted oil cooler) |
3. Ergonomics, Range & Scheduled Service Intervals
| Displacement · Max Power · Peak Torque | 1170 cc · 109 hp @ 7,250 rpm · 116 N·m (85.6 lb-ft) @ 6,000 rpm |
|---|---|
| Seat Height & Wet Curb Weight | 805 mm (31.7 in) · 221 kg (487 lbs) |
| Fuel Tank & Est. Real-World Range | 18 L (4.8 US gal) · ~19.6 km/L → ~353 km (219 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: 10,000 km |
4. Generation Cutoffs & Real-World Wrenching Gotchas
Model-Year & Chassis Generation Notes
Across Euro 3 (2014–2016), Euro 4 (2017–2020), Euro 5 (2021–2023), and the redesigned 2024+ R 12 nineT (KR1, 16 L tank), every generation preserves the legendary 1,170cc air/oil-cooled DOHC Boxer with a dry single-plate clutch and three separate oil cavities.
Oil & Clutch Mechanical Engineering Note
Unlike wet-clutch water-boxers, the R nineT runs an automotive-style dry single-plate clutch with three isolated fluids: 4.0 L of SAE 15W-50 engine oil (filter 11427673541, NOT 779), ~700–800 ml of SAE 75W-90 GL-5 transmission oil, and 180 ml of rear bevel-drive oil.
Garage Wrenching Gotchas
- Standard K21 R nineT center-laced wire-spoke wheels require inner tubes (tube-type)! Only cast wheels (Pure), cross-spoke rims (Scrambler/Urban G/S), and Option 719 tubeless wheels can be plugged with a tubeless tire kit.
- Twin-spark cylinder heads take 4 spark plugs (
NGK MAR8B-JDS, 2 per cylinder)—and never slip the automotive-style dry single-plate clutch at high rpm on hill starts, or you will glaze and burn the friction disc.
5. Frequently Asked Questions (FAQ)
How many separate oils need changing on a BMW R nineT?
Three separate cavities: 4.0 L of SAE 15W-50 in the engine (every 10,000 km), ~700–800 ml of SAE 75W-90 GL-5 in the separate 6-speed gearbox (fill to bottom of filler threads), and 180 ml of SAE 75W-90 in the rear shaft drive.
Can I use a tubeless tire plug kit on standard BMW R nineT spoke wheels?
No—classic center-laced spoke rims on the standard K21 R nineT run inner tubes. Only cast-alloy (Pure), cross-spoke (Scrambler), or Option 719 tubeless rims accept tubeless plugs.
Why is replacing the battery on a K21 BMW R nineT notoriously tricky?
On K21 models, the YTX14-BS battery is buried underneath the rear of the 18 L aluminum fuel tank, requiring tank removal or lifting—always keep a maintenance lead or CAN-bus charger handy.