sdmc530, I'm not trying to belabor the point; I add this in case others might find some utility in it. I have glasses with bifocals, too. What I found was that the reading prescription in the bifocals was inadequate for a quick glance at the cycle computer. A jump up to +2.50 worked well for me. I also found that I could trim them down quite a bit and place them in towards the nose piece (in what a proper optician would likely insist would be 'cross-eyed') and they worked very comfortably.
Getting olderer does suck.