TerryU said:True, but who knows today whether or not circumstances would require you to bike in the dark in Montana? Montana law also says you have to have a clear reflector in the front; red in the rear; a light front and back visible for 500'. And who has ever turned their headlight on and paced 500' to see if it complies with generally accepted state laws.
I'm coming from the mouth of the Columbia River and I have no idea what kind of cops patrol in Montana or what the fines are.
Back to your original question (my response above is not helpful, sorry). I might be mistaken, but the spoke reflectors that come with the bikes I've purchased, I THINK, would work on the flat Aksium spokes (I also have Aksium wheels). Have you tried them?
Something I thought of as I was tinkering with my bikes last night: I do know that the spoke magnet for my bike computers works with the flat spokes. If you're in a pinch, you could buy extra spoke magnets (cheap) for your front and rear wheels and epoxy a reflector onto that. I would think that a good, strong epoxy, properly applied, clamped, etc, would hold a light plastic reflector onto a wheel. If you're in doubt, you could use two spoke magnets for each reflector. The question would then be - would they interfere with your computer magnet pickup that you have strapped to the fork? Maybe not if they're on the opposite side of the wheel.
Some other ideas:
Do they make road tires with reflective side walls? I recently bought some street-use MTB size tires with reflective side walls.
Could you glue some thin reflective material to several places on the tire side wall (not the rim, the tire)? 3M makes a variety of colors of reflective tapes for industrial vehicle use and I have no doubt you could figure out a way to stick or glue hem to the sidewalls without upsetting the balance of function of the wheel. The stuff I'm thinking of is very thin tape type material and once stuck, is very tenacious if not permanent. A few smallish pieces distributed evenly around the wheel would give you the square inches and visibility you need, especially when the wheel is turning and the pieces would blend into a round reflective appearance. Check out a "safety supply" type store for this stuff or yahoo "reflective tape".