Jolle wrote: β04 Apr 2021, 08:48
.... By the way, they can't change the shape of the impact foam to any specific driver without homologating that exact fit. So, the whole 3D scan thing is a lot of marketing hoha. They can only change the inner lining a bit.
True ....
changing the shape of the impact foam can be done (like panel beating) - this is a good thing
changing only the shape of the inner lining gives a cosy feeling - but is a bad thing
because keeping the helmet properly located in a crash requires the impact foam to be the same shape as the head
remember 50% of purchases give too much impact foam - eg if there's 3 shell sizes but 5 or 6 'helmet' sizes
more like 100% in the EU of course - this wrongly (said the Snell Foundation) having 2 grades of impact foam
(btw the bigger EU shell increases fatigue and neck-twist effects - which their regulations arbitrarily ignore)
so there's no penalty in helmet efficacy (only benefit) from a bit of interior panel beating