Originally Posted by Don Coyote
So that rectangular piece in the supplied liner is what folds in or out to cover the holes for winter riding? Does the replacement have anything to cover them?
Reading the webBikeWorld review of the C3Pro, they classify it as shaped slightly to the inverse-egg side of neutral, implying that the decreased abduction rate comes from the poor seal formed around the bottom and resulting 'booming' turbulence noise on those with egg-shaped heads.
Correct, the 1”x 1” (rough guess) Grey square in the standard liner was designed to keep cool air from seeping through to riders heads. The optional replacement crown liner does not have one. It relies on the open/close mechanism on the top vent. How effective the Grey square (for lack of a better term) is, will be subjective. If a rider is sensitive to cooler temperatures, it will come into play more.
The C3 and C3 Pro are both on the round side. I have an intermediate oval headshape (I’m an egg-head
) and neither helmet fits me well. I have a lot of space in back of the neckroll. If the helmet does not fit evenly throughout the crown, cheeks and neck the rider will undoubtedly hear heavy buffeting / turbulence at speed.