Really sorry, i'm in France, I don't know Russian and my English is very weak, but there is the translator, also, I hope that someone can help me in this language !
I restore with difficulty a motorcycle bought in September 2019: Иж Юпитер 3 year 1973. This bike is coming from Lettonia, but this make and model was imported to France at the time 1973/1975, however there are really few. At the time, she was 15 years late, but I liked her look very much !

I have the operation repai book in English, but but it's pretty little detailed, and impossible to get help on the forums here !
I have the plan to restore it thoroughly, but it will be long and difficult because in fact, it has rolled a lot, and there is wear everywhere.
I start to reassemble the engine and the gearbox, and the frame of the bike is totally bare, which allowed me to see that it had a small defect ...
In fact, the horizontal tubes are not perfectly square with the vertical tube that goes from the steering to the engine, the right side of the frame is 3/4 mm lower than the left. No trace of shock, repair, except the lower tube above the axis of the brake pedal that was apparently very flattened to accommodate the pedal.
My question is simple: Is it possible given the quality of this period, that this defect is original ? (As a result, the rear wheel is not perfectly vertical when the bike is straight).
I will have on other issues that will come, but this matter of framework bothers me, and it is very, very expensive to have straightened!
Thanks in advance if you can help me.
[img

Alignment is different.

very flattened tube above the brake pedal axis...It seems original.

the tubes are not at 90 degrees
