I've found some BMX levers from an old bike, and just ordered some nashbar risers.. If they both use caliper brakes, would they work? I'm just afraid it won't fit on the bars?

I know a guy who has a BMX lever on his risers.

Yeah, I run a BMX lever and brake. On bullhorns though. I had to get a longer screw to attach the lever, and it works great and good. Looks sexie too.

after getting over some knee issues, I rocked platforms with dual brakes and bmx levers.

I as well run BMX levers without problems, ran em on my drops and on my horns, now i dont have a brake, but hopefully I will as soon as I go pick up a smaller caliper from home, and it will probably be going on risers. I like them because the levers I use are like the green one posted above and are easily taken off or put on.

I run risers and a BMX lever

if your using a 25.4 clamp bar, you shouldn't have a problem fitting a BMX lever, depending on how much you chop em', and where the taper starts on the bar. I couldn't run this lever with a flat MTB bar, as the center bulge goes out MUCH farther from center on a flat bar.

yo, also, those levers I got on there are hinged too.

Check out the tech 77's if you want some hinged levers taht you can bend too.