Hello Phifi, you are right!
What I wanted to say is that the advance before PMS ( the highest point reached by the piston) is fixed in 17° at idle (1350 RPM) and use this value and my maximum RPM as a reference. With 17° fixed advance...my bike couldn't go so far with RPM!!
What I wanted to add, is that TZR 125 R has a variable advance CDI (same of TDR, as you know), but the advance "curve" in the upper-end allows higher RPM (about 1000 RPM more) that the TDR, due to the smaller carburetor 28mm (TDR) VS 32mm (TZR 125 R) and different exhaust, can't reach.
The electrical circuits of TZR 125 R are slightly different (newer) from the TDR's one (heredity of DT 125 R) although the code (3MB) is the same.
The best variable advance CDI and electronics came with TZR 125 R SP and TZR 125 RR, with code "4DL".