Above on the page there are several PDF Manuals for CHANG-JIANG Motorcycles.
The CJ750 or Chang-Jiang is a motorcycle whose original design dates back to 1938.
Unfortunately, it is not assembled with the meticulousness of its original predecessor, the BMW R71.
When you buy one you have to realize that it is a motorcycle from 1938. You have to like tinkering and tools are always with you during the rides.
Every time you want to go for a ride, you have to run the engine and check it.
Oil level, tire pressure and any loose parts. If you use the bike as a veteran, you have a bike with a beautiful appearance and a good story for a price that you buy few other classic motorcycles with sidecars for.
Better not buy a Chang Jiang if you actually want a BMW.
It is not a copy of the BMW R71 but a copy of the Ural M72. That is a copy of the BMW R71.
The first Chang Jiangs were built around 1957 from parts from Ural. Later, the entire production line was moved from USSR to China.
Under pressure from the military, the Chang Jiang has received some adjustments in its career that the Ural and BMW never had. The most notable is the starter motor and ignition mounted outside the block.
Top speed can sometimes be close to 100, but you just don't want that. When you think of the word speed, buy it a Japanese.
Also overhead valve BMWs are quite easy to find for a decent amount. You don't buy Chang Jiang to get somewhere fast. Nowadays a new one costs more than 6000 euros.
By new we mean "refurbished". This means that a used motorcycle is built with as many new parts as possible around a frame from before 1965.
All engines are originally from the military. It is quite possible to find a neat (new) example for less that sometimes still needs to be broken in.
Many Chang Jiangs stand idly in sheds waiting for a new owner. That usually has a reason. Parts are plentiful.
You can also look for a Ural or Dnepr block, they also fit and are sometimes cheaper. Parts are often interchangeable. If you want to increase reliability, it is doable for the good mechanic to build in a BMW block OHV.
But then you better buy a BMW right away. Do the same if you want to go faster than 80 or 90.
People often look at this brand and these engines with a bit of pity, but you just have to have paint on it.
It's a beautiful machine with a long history that you can have a lot of fun with and it remains something special.
Fortunately, the internet is full of enthusiastic enthusiasts all over the world.
Of course everything depends on the purchase price and the condition. For the current prices you cannot make demands that you can make of a Japanese or European twice as expensive.
What you buy is a hobby and a classic with a lot of character as we call it. An engine that you can have a lot of fun with, without being bothered by all the electronics and fashion gadgets of other brands.
Parts are plentiful and cheap to find. With some love, attention and sensible handling of the old iron, you can enjoy many years of fun.