It's the SL-500 model (flat bar) i believe. As usual google's got tons of stuff, but nothing relevant that i can find. With similar looking shifters the thing seems to be to undo the allan nut holding the lever on to the body, but if i do, it just turns and nothing happens. The lever seems as attached as ever and i don't want to force anything. Can anyone please tell me what to do before i screw something up? Thanks.