On old, but still very common mopeds such as Riga-11, Riga-13, shock absorbers are only on the front wheel, while the rear wheel is rigidly mounted. When driving on country roads, the rear wheel and the frame “catch” all the bumps and therefore the rim cracks very quickly, nuts are unscrewed from strong vibration, cracks appear on the frame, and riding on such a moped turns into a real torture.
With a welding machine, the good old "gas-lu" can be improved.
The first step is to cut off the entire back of the frame. Just cut everything very carefully, because you will make the new “pendulum” out of the old moped fork. Weld two round steel cheeks with a thickness of 3 mm to the ends of the cut fork on both sides and place a spacer sleeve with a diameter of 20 mm in them. Then weld two bolts at the back of the fork, which will serve as fasteners for shock absorbers. The new plug is almost ready. Now you need to weld the mounting sleeve to the main frame. You can make it from a pipe with a diameter of 22 mm and with a wall thickness of at least 2 mm.
If everything worked out fine, make seatpost brackets, weld bolts to them and screw the shock absorbers. For greater strength, weld a reinforcing scarf between the frame and the moped seatposts. You can make it from a metal corner or sheet steel 1.5 mm thick.
If you are modifying a Riga-11 moped with a fuel tank under the rear trunk, you will have to transfer the tank to the moped frame.