I wear a fair amount (not Mr. T or anything) of jewelry off the bike, but before a ride it all comes off except for the diamond studs in my second earpiercings (these never come out). I don't like the feel of rings or bracelets in my gloves or earrings rubbing/catching on helment straps. I don't guess a necklace would bother me, but since everything else is coming off -- it does too!