dminor 

I used to be a firm believer in moto helmets for downhill and used a SixSixOne Hurricane Flight for a couple or three years. There have been two schools of thought on the subject: I originally switched because, at the time, more and more team managers were wanting their racers in moto helmets because of the potential for high-energy crashes nearly or as severe as one on a moto. Plus, I came from a moto background, where Snell is the holy grail; so I wanted to get back to a Snell helmet. (BTW, as far as I'm concerned, a DOT cert is meaningless. If you've seen those 'puddin' bowl' pieces of crap that a lot of Harley riders wear, you'll see that, somehow, those jokes-for-helmets are DOT certified). For my money, SMF cert is still the only way to go on a moto.

Later, I got into a good, spirited discussion of moto vs. bike full-face helmets on another forum with Sean Estes (Easton-Bell Sports) who sat on the ASTM board that drew up the ASTM 1952 standard. Thier contention is that there was a lot of evidence that moto helmet shells are almost too stiff and non-compliant for anything but an extremely high-speed moto crash - - and that the bike full-face should not be quite as rigid (think crush-zones). I didn't want to believe him at the time; but I did more research on my own, went over his arguments again and the reasoning eventually won my over. My next helmet was an Evolution Carbon, which served me well before giving up its life for me this spring. I'm now using an Urge Down-O-Matic, which does not right now carry an ASTM certification but does meet CE1078, which is reputed to be almost as rigorous of a standard as Snell B95.