im sorry for not explain this item because my inglish is lamentable and i cant undersantd your questions...
but this front fork upgrade is necesary for torsion effect produced when you brake or take a hard curve....((nein menos mal q les has dicho algo por que no tengo ni papa de ingless y esto es pesimo)) this is the spanish explain ^^ sorry again...
http://www.xt660.com/showthread.php?p=65549#post65549
its a laser product the most economic solution for torsion effects when i changed xtr>>>>xtx
i dont know any people what had needed this item and i dont konw if this problem is in all changes.