Originally Posted by
noglider
Not an answer to your question, but you may want to consider a helmet- or eyeglass-mounted mirror. I use the Take-a-Look mirror and attach it to my glasses. Some attach it to their helmets. It takes some practice to use well, but I really like it. It's also pretty sturdy. It folds up, and I can put it in my front pocket.
I’ll second that opinion, if just for the record. I’ve knocked off and broken the couple of handlebar mirrors I have used. Just this weekend I further wrote about eyeglass mounted mirrors in a thread on the Road Cycling Forum,
”Accident avoidance” regarding crashes in pacelines.
Originally Posted by
Jim from Boston
+1 to a mirror, especially helmet and eyeglass mounted, as I wear. Jim's Law of the Road is ”No matter how well-paved or lightly-traveled is the Road, a vehicle is likely to pass you on the left, as an obstacle occurs on the right (or in front).” The OP describes a most spontaneous and unanticipated hazard, and I think a head mounted mirror offers the quickest and least head/eye movement to assess the rearward traffic situation, compared to handlebar mirrors.
Also, a mirror allows easy periodic rearward checks, so in a quickly hazardous situation, one may already know the coast behind is clear, to take avoidance maneuvers.
One other problem I noted with a handlebar mirror is that when I stand to pedal, the rearward view is lost. Finally, one consideration, no matter what kind of mirror, is to wear
two,
right and left.