What was found
AIRCRAFT NOT GROUNDED: PILOT REPORTS UNCOMMANDED DUAL ENGINE ROLLBACK AT 900 ON TAKEOFF 10 PERCENT ROLLBACK PRIOR TO VNAV ENGAGEMENT. MAINTENANCE REPORTS RESET, ACCOMPLISHED BITE CHECK ON MMR 2 IAW FIM 34-31-00-810-801. ACCOMPLISHED EEC BITE IAW FIM 73-00-00-810-801-F00, NO FAULTS NOTED. ACCOMPLISHED A/T BITE CHECK IAW FIM 22-31-00, NO FAULTS NOTED. ACCOMPLISHED FMC BITE CHECK IAW FIM 34-61-00, BITE CHECKS GOOD. ACCOMPLISHED DFCS BITE CHECK IAW FIM 22-11-00-810-801, BITE CHECK GOOD. A/C OK FOR CONTINUED SERVICE.