http://www.smf.org/

Why should you replace your helmet every five years?
The five year replacement recommendation is based on a consensus by both the helmet manufacturers and the Snell Foundation. Glues, resins and other materials used in helmet production over can affect liner materials. Hair oils, body fluids and cosmetics, as well as normal "wear and tear" all contribute to helmet degradation. Petroleum based products present in cleaners, paints, fuels and other commonly encountered materials may also degrade materials used in many helmets possibly degrading performance. Additionally, experience indicates there will be a noticeable improvement in the protective characteristic of helmets over a five year period due to advances in materials, designs, production methods and the standards. Thus, the recommendation for five year helmet replacement is a judgment call stemming from a prudent safety philosophy.

 

The post above stating that since 1974 all helmet manufacturers must stamp the month and date of production on the chin strap is incorrect.

 

I also heard 5 years. If I had an older helmet in good shape I'd wear it.

 

same here! just peeled back my liner. date is 12/1991. i new it was old. thx guys!

 

If I were a helmet manufacturer and made my living selling them, I think I would tell you that you should get a new one too... Just sayin'

 

30 second internet search yielded this snippet from the Motorcycle Safety Foundation. Hope it helps:

"...Inside the shell is the equally important impact-absorbing liner, usually made of expanded polystyrene (commonly thought of as Styrofoam). This dense layer cushions and absorbs the shock as the helmet stops and your head wants to keep on moving. Both the shell and the liner compress if hit hard,spreading the forces.

Most helmet manufacturers recommend replacing your helmet every two to four years. If you notice any signs of damage before then, replace it sooner.

Why replace your helmet every few years if it doesn't appear damaged? Its protective qualities may deteriorate with time and wear. The chin strap may fray or loosen at its attaching points; the shell could be chipped or damaged.

The best reason is that helmets keep improving.Chances are that the helmet you buy in a couple of years will be better – stronger, lighter, and more comfortable – than the one you own now.It might even cost less! (202) 366-4913;www.nhtsa.dot.gov/..."

Snell Memorial Foundation,Inc.
3628 Madison Avenue,Suite 11
North Highlands,CA 95660
(916) 334-5073;www.smf.org;info@smf.org

 

i have had old helmets sitting around that the foam behind cloth inside degraded to dust and the styrofoam seemed much more compressed/brittle.
On one helmet the stitching on the strap d-ring just degraded and broke OFF.
Took 7 to 10 years.
I would think once that cloth liner inside starts to go (about 5 years) it is time to replace.

 

Imagine that. A HELMET manufacturer recommending replacing your helmet every two to four years.

 

Why would you want to take a chance on a 27yr .old helmet?
Helmets are not that exspensive.

 

Depends on how it has been used and stored IMO. However, I'd say that 27 years is time to replace and buy a new one.