I'm going to go out on a limb here and say that there are probably better things these days than those old reflectors (reflective technology has come a long way recently).... why not get rid of them and put on something less dorky and more effective.

The reflective side wall tires you put on are very good. I went out with a bunch of people last year and we tested various lights and reflectors. We did find that for the most part reflectors still rule - they are brighter and more noticeable than lights (in fact #1 best light up the night item...... dorky orange traffic triangle!).

One light we did find quite good (and this was a surprise) was a tirefly - the kind that replaces your valve stem cap and blinks as it goes around. Hokey spokes sound more fun than plain old reflectors. How getting about getting really creative and using ultra reflective 3M "Diamond Grade" to make some reflective spoke cards. It comes in 4 or 5 colors and can be easily cut - in fact you can get precut reflective stickers right here on this web site. (though I'll bet most fixie riders would think it totally uncool ...)