last winter i looked into the idea of making some simple drop links that are lockable, didn't search but wouldn't surprise me to see others have tried this. Once i got going, about 50 designs later, i wanted to see if i could design the greatest drop links ever, too much time on my hands i guess. here it is. lockable for road + dual twist. bottom twist is what you've seen before to let the springs twist, the top twister kicks in ONLY as the link drops,(more drop = more twist), letting the entire axel roatate on it's natural arc similar to quarter eliptical. I did weld up a proptotype but haven't tried it out yet, my kick is already too high and flexes plenty. I did have dreams of selling a few but they take so much time, not sure it would be worth it.