As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BURNING RUBBER ODOR IN COCKPIT AFTER ENG START, AS TAXING OUT SEEMED TO DISSIPATE. AS ACFT TOOK RUNWAY FOR TAKEOFF, ODOR CAME BACK VERY STRONG, AGAIN IT SMELLED LIKE BURNING RUBBER. PERFORMED CONDITIONAL INSPECTION FOR SMOKE & ODOR IAW AMM 05-51-58. NO ODORS OR SMOKE NOTED. TAKEOFF POWER TEST NR 13 WAS PERFORMED IAW AMM 71-00-00-715-223-R03, COULD NOT DUPLICATE ODOR.