Oh, my bad. I just skimmed ya'lls posts and and mis-read it.
Frankly, if you're fighting frame-flex on a spiney, it's a loosing battle. I do, however, recall a Japanese sight that had some aftermarket frame stiffening bits. Try this:
http://www.guzzisport.com/html/v11taisaku.html
I don't read kanji, though, so I can't help you much. They have some really trick bits for the various models.