The speed regulator trick works...up to a certain extend ...
All of a sudden...no more ....and the A-11 ( same for all mech. movements) picks up speed or loose pace...and...gone...!
Then ...only a routined an skilled watchmaker can help...if...he knows and has the balance and other worn out parts...
Mine...in Europe...in Germany...Meister Hemmerling...in Calau....( already posted here) but...not a cheap Charley..( .a matter of priority......Crapola or the real thing..)...but very skilled and with all needed parts...
In Korea...( also already posted here) I have another one, but maybe not relevant here...unless someone wants to send his watch to Korea for repair.