TwoTired, do you wear a helmet?...'cuz that is gonna muffle your hearing considerably. Might be much safer to not wear a helmet so you can hear the dangers waiting to spring at you from all sides. Do you limit your riding to under 40mph? ...cuz wind noise after about 45 is really loud and you are not gonna hear anything over it anyway.
Of course I wear a Helmet and said so previously. There's a helmet law here in California, as well as a law regarding ear plugs. I'm also well aware of the damaging effects of loud noise and the need to protect your hearing from that.
Still, a helmet alone accounts for only a 2-3 db attenuation factor. Foam ear plugs attenuate in the 30-35 db range. And that matters in city traffic or how soon, distance wise, you will hear a car horn or a emergency vehicle siren.
If your motorcycle makes 100db. You are unlikely to hear the 100db horn of the car screeching into you until it's 2ft away, irregardless of helmet or earplugs.
If your motorcycle is making 70DB, a 100DB car horn can be heard from farther away if wearing a helmet, than wearing 30-35 db earplugs. With ear plugs you may notice metal bending and bones crunching before hearing of any warning sound. In effect, you are restricting your own sensory input to sight only, which is hardly a survivalist technique.
At any rate check your laws. Can't wear ear plugs in both ears here in California, unless you are "special".