BMW R 23 (1938–1940) — Specs
Identity
Manufacturer: BMW
Model: R 23
Category: Motorcycle
Type: Motorcycle
Years: 1938 → 1940
Engine
Displacement (cc): 247
Cylinders: 1
Power (hp): 10
Power (kW): 7.3
Torque (Nm): 12
Dimensions
Overall length: 2070 mm
Overall width: 770 mm
Overall height: 1130 mm
Wheelbase: 1395 mm
Ground clearance: 155 mm
Weight (kg): 135
Seat height (mm): 690
Tank (L): 9.6
Drivetrain
Final drive: Shaft drive
Ignition
Spark plug: NGK B6HS
Plug gap: 0.7 mm
Fluids & Filters
Engine oil (with filter, L): 1.5
Oil filter: OEM oil filter
Air filter: OEM air filter
Brake fluid: DOT 4
Fuel consumption
Estimated range: ~320 km on a full tank (9.6 L)
Service
Battery: OEM battery specification
Service interval (km): 6000
Service interval (months): 12
Valve check (km): 12000
Parts and consumables for this motorcycle
Data is gathered with care, but without guarantee. Always confirm critical information with your dealer or workshop.
Service notes
Service interval: every 6,000 km or 12 months, whichever comes first. Valve clearance check every 12,000 km. Valve clearance — intake cold 0.10-0.15 mm, exhaust cold 0.15-0.20 mm. Engine oil: 1.5 L with filter change. Spark plug: NGK B6HS (gap 0.7 mm). Drive: shaft drive. Always confirm critical values with the workshop manual or an authorised dealer.
OEM and quality aftermarket parts that fit this bike. Always confirm with your dealer before ordering.
Engine oil
Spec: nan, 1.5 L (with filter)
- OEM OEM recommended engine oil
- Premium Motul 7100 4T (100% Synthetic, Ester)
- Premium Motul 5100 4T Technosynthese (Semi-Synthetic)
Which Motul for this bike?
| Motul 7100 4T ✓ | Motul 5100 4T | |
|---|---|---|
| Product | Motul 7100 4T — 100% fully synthetic | Motul 5100 4T — semi-synthetic |
| Best for | Sport, Naked, Adventure (600cc+), track | Standard, Cruiser, Scooter, daily use |
| RPM protection | Excellent — ester base, stable under load | Good — for normal riding conditions |
- Standard Repsol Moto Racing 4T (Synthetic)
- Standard Elf Moto 4 Tech (Semi-Synthetic)
Fully Synthetic vs Semi-Synthetic
| Fully Synthetic | Semi-Synthetic | |
|---|---|---|
| Base oil | 100% chemical synthesis (ester or PAO) | Mineral oil + synthetic additives |
| Heat resistance | Excellent — stable at extreme heat & RPM | Good — suitable for normal temperatures |
| Cold start | Better — reaches engine faster when cold | Good — adequate for normal climates |
| Change interval | Longer (up to 10,000 km) | Shorter (5,000–7,000 km typical) |
| Price | Higher | Lower |
Oil filter
Air filter
Spark plug
Spec: NGK B6HS, gap 0.7 mm
- OEM NGK B6HS
- Premium NGK BR6HIX
- Standard NGK B6HS
Front brake pads
Spec: EBC FA086HH
- Premium EBC FA086HH
Rear brake pads
Spec: EBC FA086HH
- Premium EBC FA086HH
Front tire
Rear tire
Battery
- Premium Yuasa YTX7L-BS or YTX7A-BS (typical 125-250cc)
Brake fluid
- Standard TotalEnergies HBF4
Coolant
Service interval
Spec: 6 000 km / 12 months
- OEM Engine oil + oil filter change
- OEM Air filter inspection
- OEM Spark plug check
- OEM Brake fluid replacement: every 2 years
Valve check
Spec: 12 000 km
- OEM Intake clearance: cold 0.10-0.15 mm
- OEM Exhaust clearance: cold 0.15-0.20 mm
Suspension
Spec: TELESKOPGABEL / 150-170 ml
- OEM Fork: TELESKOPGABEL
- OEM Fork oil grade: 150-170 ml
Drive chain
