The G/S doesn't have a high compression ratio, so 130 doesn't sound bad to me. The more important thing is comparable figures side to side, which you now have.
My guess is there was carbon build up you blew out, that was sticking the rings.
Wanted: Dead, smashed, crashed or trashed gauges
BMW GAUGE REPAIRS - TACH*SPEEDO*CLOCK*VOLT METER *PODs & LIGHT BOARD*