i'd gear the motor a bit softer say 44mm role out
im a noob but at a certain point the motor will over heat and either desolder or throw a wind due to the resin on the armature. both are rare and unlikely but that few tenths a lap are well lost if u finish
just my 2 cents
id run several fans by the way with the best heat sink u can find its worth it cause u can chase em down at the end when their motor ffades just make sure u know how long u can run on a pack after all soon as it dumps your loosing precious time.
to make Keith happy