Researchers at the University of Florida tested 33 motorcycles. And at full-throttle, they all produced noise levels above 100 decibels   the equivalent of a loud rock concert or a chainsaw. And noise above 100 decibels is safe for only 15 minutes. Even at 85 decibels, continued exposure can lead to permanent hearing loss.

The loudest motorcycle they tested hit 119 decibels a noise level that begins to damage your ears after just 11 seconds. In fact, if you ran a motorcycle engine next to your desk at work, the National Institute for Occupational Safety would require you and all your cubicle-buddies to wear ear protection.

What about motorcycle helmets. Don't they protect your ears? Nope. Foam earplugs can reduce sound levels by maybe 25 decibels   but for the loudest bikes, even that won't protect your ears.

So, how do you know if noise is damaging your hearing? Here are a couple warning signs: Your ears ring when the noise stops, and continue ringing for several minutes, hours or days. And the voices and sounds around you start sounding muffled.
If you'd like more information about noise-induced hearing loss, check out FamilyDoctor.org.