XING RESTR NOT MET DURING ARRIVAL AT HONOLULU; HI.

Narrative

I WAS RETURNING TO HONOLULU ON AN IFR FLT PLAN; ABOUT 5 MI E OF THE MOLOKAI VOR ON V-8 AT 8000 FT. I RECEIVED THE FOLLOWING INSTRUCTIONS FROM CTR: 'ACFT X DSND TO 6000 FT PLAN TO CROSS LOKI INTXN AT 4000 FT.' I BEGAN A 1000 FPM DSCNT AND REDUCED PWR. I ENTERED SOME CUMULUS BUILD-UPS AT THIS POINT AND WAS EXPERIENCING LIGHT TO MODERATE TURB. I SLOWED MY DSCNT RATE TO 500 FPM TO SLOW AIRSPD. CROSSED MOLOKAI VOR AT 6500 FT STILL PLANNING TO CROSS LOKI INTXN AT 4000 FT. THERE WAS A 20 KT TAILWIND; MY GND SPD ABOUT 230 KTS. WELL; THINGS DIDN'T WORK OUT LIKE I HAD PLANNED AND I CROSSED LOKI INTXN AT 4800 FT. THINKING BACK ON THIS SIT; I'VE FLOWN THIS SAME RTE AND SAME DSCNT PROFILE AT LEAST 20 TIMES CORRECTLY. WHY DID THINGS GO WRONG TODAY; AND WHAT COULD I HAVE DONE DIFFERENTLY? IT IS CLR TO ME NOW THAT AS SOON AS I ENCOUNTERED TURB I SHOULD HAVE NOTIFIED ATC OF MY SIT. I COULD HAVE GOTTEN AN AMENDED CLRNC; BUT I CHOSE TO PUSH ON THINKING I COULD MAKE THINGS WORK OUT. NEXT TIME I FIND MYSELF IN THIS SIT I WILL SPEAK UP.