History of the Chang Jiang 750 Motorcycles
The CHANG JIANG 750 motorcycle is the Chinese clone of the Russian M72, which itself is the clone of the BMW R71. After the Russian's successful cloning and use of the R71 during world war II, a few of their version of the motorcycle (the M72) were sold to the Chinese during the 1950's.
In 1957, the Chinese started their own M72 production under the name of CHANG JIANG 750. In the 1960's, the factory name changed to "GUO YING CHANG JIANG JI XIE CHANG," and then in the late 1970's was re-attached to airplane manufacturer, GUO YING HONG DU JI XIE CHANG, known in the 1990's as NAN CHANG FEI JI ZHI ZAO GONG SI, and today as JIANG XI HONG DU HANG KONG GONG YE JI TUAN.
The early CHANG JIANG 750 motorcycle production was made by the GUO YING GAN JIANG JI XIE CHANG. The early production used many Russian M72 parts, such as fenders, frames, wheels, ignition keys, switches, etc...
Even some complete Russian-made M72 were later renamed CHANG JIANG 750, and in some, the Russian engine was replaced with a Chinese-made engine.
One method of distinguishing the Chinese-made casing from the Russian is that the Russian-made casing is smoother. Other differences can be noted on the frames of the bikes and sidecars. Chinese front fenders differ slightly from the Russian in that the brackets are fastened with bolts and screws, whereas the Russian are one piece and fastened by rivets.
Up until the end of the 1970's all Chinese CHANG JIANG 750 series were mainly powered by 6 volts engine of two types: the CHANG JIANG 750 TYPE I engine, similar to the R71 and M72, identifiable by the dipstick at the bottom of the engine, and the CHANG JIANG 750 type II engine, of which production began in September 1966--identifiable by the dipstick at the top of the engine. (All engines with the serial number 661802 and after are Type II engines.)