Does anybody know what the time line is on a helmet replacement? I use as a rule if you have a major crash it should be replaced. If you can or can not see out side damage. My question relates to they are rated in 5 year cycles on snell/dot 1995 - 2000 - 2005 ratings ect. I know in some road racing or autocross if you helmet is over 2 cycle years (meaning snell/dot 95 will not be able to be used) you can not use it, so in motocross if it becomes 5 years old would you replace it even if it has not been crashed? I know in inside shell/foam stuff is the concern, but anybody who can shed light on this i thank you. Plus I jut got 2 more helemts to replace 2 that are 4-5 years old.