Helmet Shelf Life
Yesterday, a fellow rider came by the house. He was debating whether he would join Terrie and I for dinner since it would be dark in several hours and he had his dark shield on his helmet. I offered to let him borrow my clear shield if it became too dark since I had recently installed a light smoke shield on my helmet.
He promptly said it wouldn't fit since he had an Arai RX 7. I told him I had the same helmet and it should fit. He immediately picked up my helmet and started examining it for date of manufacture while asking me when I purchased the helmet. He said an older helmet wasn't as good as a newer helmet.
I told him that both Arai and Shoei both warranty the integrity of the helmets from the date of sale and that I was aware I was purchasing an older RX 7 at the time I purchased the helmet.
After he left, however, I decided that the fact that a warranty existed did not really answer the question of whether an "older" new helmet was as good as a "newer" new helmet. So, I did some research.
Some on the motorcycle forums felt that a set rule of 5 years from date of manufacturer should be followed regardless of whether a helmet was new or used. Others took the position that a helmet was fine, even though it was 20 years old as long as it had not suffered an impact. Some believed that helmet shelf life restrictions were invented by helmet manufacturer marketing people as a ploy to get you to buy a new helmet every few years.
Here's what I found from my research:
First, since 1974, all helmet manufacturers are required to stamp the month and date of production on the chin strap. It is not unusual for a new helmet to arrive at a retail store with a 1 to 2 years or more older production date. I think a good rule to live by might be to purchase a new helmet if your helmet is pre-1974 and has no production date stamp on the chin strap.
Second, I think you should examine the safety standards that were in place when your helmet was manufactured. In general, the newer standards are more stringent and allegedly produce a safer helmet. If you have a helmet that was manufactured when there were few or lesser safety standards, you should consider purchasing a new helmet.
Finally, I think you should examine how the helmet was treated, worn and maintained. Is the helmet used frequently? Is the helmet left in a hot garage or storage area when not in use or left exposed to the elements? Is the helmet regularly cleaned and maintained removing grime, body oils, etc? Does inspection of the helmet reveal any faults such as a frayed chin strap or indentations/compression of the inner shell? Has the helmet suffered any impacts?
I think the factors listed above are important in deciding whether to buy a new or used helmet and to determine whether a new helmet with an older production date is the right helmet for you.