I recently purchased a new AGV helmet. I’m either a sucker for propaganda, or acutely aware of the diminishing performance a helmet gives with the passing of time. Back in my younger days, where riding the motorbike was a daily occurrence, I tended to replace my helmets every couple of years to avoid the problem of compressing the lining. These days, I am more of a “weekend warrior” and hence only feel the need to replace the helmet after about five years.
I don’t think I will ever be the sort of person who purchases a helmet on-line. I need to know that it will fit well and that things like the chin strap can be easily tucked away. Things you can only really tell by examining and wearing the helmet. The consequences of picking the wrong one on-line deter me from doing so!
Even though I prefer the “real life” selection process, the one question that always remains unanswered is: “Will this helmet be quiet?” I suspect I shouldn’t bother asking as the honest answer will always be “no”. It occurred to me as I was riding to the bike shop (to purchase “the new lid”) that when I first purchased my previous helmet, I found it disappointingly loud. However, on the trip I was taking to replace it, I didn’t think it was too bad. One could hope that as the helmet lining had compressed, it somehow improved its acoustic dampening, but I rather suspect years of ear abuse wearing the previous helmet has simply taken its toll on my hearing.
To over-simplify sound, its loudness is measured in decibels. db(A) This scale is logarithmic – as an example: an eighty decibel noise is ten times as loud as a seventy decibel noise. According to the dangerous decibels web-site once a sound reaches 85dB(A), permanent hearing damage can occur. The key thing then becomes how long you are exposed to the loud noise. For every 3dB(A) over 85, safe exposure times halve. (As a point of reference, eight hours is their suggested limit for 85dB(A) noise exposure.) Marcus, from headphones.com.au provide more generous figures, suggesting longer listening times are safe. He does work for a company that sell loud things you put on your ears, but I guess it is in his best interest to keep you hearing for as long as possible…
The Institute of Sound and Vibration Research, have recognised that noise levels whilst riding a motorcycle can be very high. Their research was carried out both in a wind tunnel and on the road. The provided measurements were hardly exhaustive, but they noted that different helmets and different motorcycles all affected the noise levels achieved. This included the revelation that particular helmets could be good or bad, depending on what model bike was being ridden. (This gives me hope, as my previous helmet started its active duty whilst I was riding my previous motorcycle!)
A provided graph showed that if you discount illegal road use (i.e. over 110kph or around 70mph) the quietest scenario was in riding a BMW K1100LT with the adjustable screen up. Even it came in at around 88db(A) meaning it shouldn’t be ridden for more than around four hours. The simplest practical answer to reducing the volume of noise you are subjected to is by wearing ear-plugs.
If you have never considered wearing ear plugs before, I recommend you get several pairs of differing styles. There are different density foams as well as “putty” like materials that mould and shape in your ears. For my liking, I can’t go past simple foam plugs that are available in chemists. Even cheap foam ear plugs reduce the volume by around the 26 to 33 db(A) mark, It may take you some getting used to the feeling of foreign objects in your ears, but the long term benefits far outweigh this initial “unnatural” feel.
Some riders prefer to listen to music via an MP3 player fitted with ear-bud speakers. But, these in turn have to produce volume louder than the wind-noise generated by the helmet. Ear-bud speakers may look trendy in the Apple advertisements, but quite simply they are capable of loud volumes and therefore are dangerous to your long term hearing ability.
If you do want to listen to music on the motorbike, I’d suggest you look at spending some serious money and get a quality set of “canal-phones” that block outside noise allowing you to use lower volumes. Just remember that there are reports that ear-buds (and presumably “canal” style headphones) can be capable of producing in excess of 110db(A).
For my money, the 70 cents or so I spend on a set of ear plugs are the simplest way I can improve the quality of my ride whilst doing something good for my long term health and quality of life.