The BMW R 68 holds a unique place in motorcycling history as the ‘Hundertmeilen-Maschine’ (100-mile-per-hour machine). Introduced at the IFMA in 1951, it was BMW’s first production motorcycle to officially break the 160 km/h barrier, a feat achieved by utilizing high-compression cylinder heads and larger 26mm Bing carburetors, distinguishing it from the more sedate R 67 touring models.
| Quick Specs: BMW R 68 – 0268/1 | |
|---|---|
| Production Years | 1952 – 1954 |
| Engine Type | 594cc OHV Opposed Twin (Boxer) |
| Oil Capacity/Type | 2.0 L | SAE 40 (Summer) / SAE 20 (Winter) or 20W-50 |
| Tire Dimensions | F: 3.25 x 19 / R: 3.50 x 19 |
| Electrical System | 6V 8Ah |
| Spark Plug | Bosch W 240 T1 (Modern: NGK B7HS) |
Engineering Analysis
The R 68 was the pinnacle of BMW’s plunger-frame era. While the chassis shared DNA with the R 51/3 and R 67, the engine was significantly tuned. The 594cc boxer featured larger valves and a higher compression ratio (7.5:1), necessitating the use of high-octane fuel which was becoming more available in the early 1950s. The cooling fins on the valve covers were longitudinal, a signature aesthetic for this high-performance variant.
Maintenance & Service Guidelines
Lubrication System
The R 68 utilizes a splash and pressure lubrication system. Given the lack of a modern spin-on filter, frequent oil changes are mandatory to prevent sludge buildup. We recommend a high-zinc 20W-50 mineral oil to protect the flat-tappet camshaft. The total capacity is 2.0 liters.
Ignition and Electrical
The 6V 8Ah electrical system is powered by a Noris magneto-generator. Timing is critical on these high-compression engines to prevent pre-detonation. The original Bosch W 240 T1 plugs are now often replaced with NGK B7HS or Bosch W5AC for better fouling resistance in modern traffic conditions.
Chassis and Tires
The R 68 features a telescopic front fork and plunger rear suspension. Handling is sensitive to tire pressure. For solo operation, maintain 1.2 bar (17.4 psi) in the front 3.25 x 19 tire and 1.5 bar (21.8 psi) in the rear 3.50 x 19 tire. If carrying a passenger, increase the rear pressure to 1.9 bar (27.6 psi) to maintain stability at speed.
Expert Verdict
The BMW R 68 is a blue-chip investment for collectors. Its combination of race-bred performance and classic German engineering makes it a demanding but rewarding machine to maintain. Adhering to strict oil change intervals and using the correct spark heat range is essential for preserving the integrity of this 100-mph icon.