I have a Pioneer PL-120 turntable which must be at least 25 years old. Have recently replaced the belt with a generic 23.5" belt. I now find that the turntable is running 2-3 percent faster than before (based on comparing quoted track times and actual running times). There appears to be two sets of speed adjusting points. Both points are marked up to adjust 33 and 45. One of the adjusting points is close to the motor pulley, and the other point is further along the rim. Looked in the handbook and no reference is made to these points. Can anyone tell me please how to proceed with the speed adjustment? Have located some strobe discs to assist me.

Thanks