I have a NZI fibreglass? helmet and was wondering, just with normal usage, roughly how long can I expect it to last before it needs changing ? I remember reading somewhere that road bike helmets need changing quite regular, because a helmet is like an egg shell and tiny cracks appear with usage, which cause the helmet to possibly break with an impact !

So if anybody has any ideas ?

Phil

The shell is not a problem unless it has visible signs of deterioration or impact damage

The shell just transfers the impact to the liner and you cannot tell if the liner has damage or deterioration, age can deteriorate the adhesive and general wear and tear just uses it up, Helmets are pretty much a one time deal, if you hit hard, your helmet has done its job and it can't do it twice as the liner absorbs the blow and is damaged

Rule of thumb is 4 years and you should replace your helmet, or if it is subjected to impact

when the odour from inside becomes toxic,its gotta go.

I wear the same helmet - had it for probably 5-6 years now, it's still fine. ( no crashes)

when the odour from inside becomes toxic,its gotta go.

Thats why a helmet with a take out liner is a good idea.The Hebo one I have is ace for this - its nice to have a fresh smell rather than an awful stink when you put it on.

I have always suspected the expiring helmet hype to merely a marketing scam pushed on us by helmet manufacturers. In some cases such as road bike helmets where you risk being struck by a car i would not argue that once its taken a large blow it should probably be replaced. In trials use I doubt you would ever need to replace it though unless it actually breaks.

when the odour from inside becomes toxic,its gotta go.