When I was hit by the Metro-Dade Bus #1042 and thrown through the air about 20 feet I was riding a Basso Tre Tubi frame with (old)Super Record Grupo and Mavic clinchers, i.e, a bicycle going about 24 MPH. My Bell Helmet saved my life. And you don't want to wear a helmet when your going 75? Just to have the wind in your thinning hair? My one and only Motorcycle accident involved dumping my 650 BSA Gold Star on some ice as I was pulling off the road going maybe 5 MPH. Went down on my knee; took off all the skin down to the bone in less than a second. And you don't want to wear a helmet at 75?