History of the cj750

To discover how a product of the illustrious Bavarian Motor Works is still being manufactured more than 60 years after its debut, you need to delve into history.

As early as the 1930's, a Russian company, Uralmoto Zavod, was producing motorcycles and sidecars in co-operation with BMW, Germany. The rising German administration of the 30's, needed military equipment, but the terms of surrender imposed under the Treaty of Versailles at the end of World War I prohibited Germany. They then developed a strategy to get around these restrictions by pursuing joint ventures with Russia. This was achieved by the signing of a 7 year trade agreement known as the Molotov-Ribbentrop pact, (also known as the Hitler-Stalin pact or Nazi-Soviet pact and formally known as the Treaty of Nonaggression between Germany and the Union of Soviet Socialist Republics). It was signed in Moscow on 23 August, 1939, by the Soviet foreign minister Vyacheslav Molotov and the German foreign minister Joachim von Ribbentrop). from any form of military vehicle production, including large capacity motorcycles and sidecars.

Despite this agreement, Germany apparently only ever willingly shared information about the then new BMW R71 design. This model was only built in Germany for a short time and in limited quantities (from 1938 to about the end of 1939); it was a migration from the stalwart Wehrmacht BMW R12 model. The R71 signalled the move away from the conventional pressed steel frame bikes to the higher strength oval tube frame design which was easily able to cope with the additional stresses of a sidecar attachment.

Germany of course, never shared the design of the newly developed successor, the BMW R75 with the Russians. The BMW R75 was introduced in the spring of 1941, built according to German war ministry instructions, without cost limitations. This high performance war machine had incredible off-road capabilities due to its driven sidecar wheel drive, locking differential, reverse gearbox and selectable low range gearbox.

The non-aggression treaty with Russia lasted until Operation Barbarossa of 22 June 1941 when Nazi Germany invaded the Soviet Union.

In response, Russia joined forces with the Allies against Hitler. By then Russia had obtained certain BMW tooling and the designs for the R71 and the Russian militarised R71 versions was renamed the M72. This was almost identical to the original BMW R71.

After the German surrender, the Allied occupation forces had “access” to the shattered remains of Germany's once impressive automotive industry. The BMW motorcycle factory, which had been relocated to Eisenach during the war (where they produced the superior BMW R75), fell into German territory occupied by the Russians. The Russians then took possession of all the BMW blueprints and tooling and shipped the few remaining BMW R75 motorcycles and all the production parts and blue prints left at the factory back to Russia. The R75 dual wheel drive system design technology was also then used to create the relatively advanced, Russian military dual wheel drive overhead-valve "Ural" and "Dnepr" models.

During 1950, the Chinese "Peoples Liberation Army Beijing No.6 Automotive Works" had been attempting to develop a suitable military motorcycle by "reverse engineering" a Zundapp KS500 military motorcycle. This machine entered production in 1951, and a total of 4248 machines were built before responsibility for the manufacture of military motorcycles was transferred to the Hongdu Machinery Plant and the Xingjiang Machine Plant. Both of these factories are subsidiaries of the State-run aeronautic manufacturing industry to this day.

Back in the USSR, now that the original side-valve model had become obsolete, manufacture of the old M72 (BMW R71-based) was offered to their Chinese communist neighbors who wasted no time in dropping the KS500 based machine for the tried and tested BMW R71/M72 design motorcycle. The BMW R71/ M72 sidecar, now renamed the "Chang Jiang" entered production during 1957 at the Chinese Nanchang aircraft factory. (It is the same as the Hongdu and the Xingjiang Machine Plants.)

Around 1985, the story goes that the Chinese, realizing that the original R71 side valve engine was now somewhat less than state-of-the-art, entered an agreement with the Russians once again, with the objective of improving the engine's performance. The Russians provided OHV engine technology, and soon an OHV 750cc-boxer engine, which is remarkably similar in design concept to the BMW /2 engine entered production at the China South Aero engine plant.

However, experts who provide maintenance on both the side- and overhead-valve models feel that the more battle tried and tested side valve models offer more reliability and suffer fewer problems. The original Hi-Torque 750cc side valve engine is therefore the model Cape Sidecars are importing at present.