I`m going to be brutally honest here, and although I would NOT recommend this to anyone else at all, it`s my honest opinion of the only way you will do it, or certainly, the only way that I did it:
I`d been riding about 3 years already, and never had the confidence to do it, although, like you, I felt I was hanging off correctly, and had all the lean angle I felt safe with.
I then bought my first Kawasaki ZX7R, and I don`t know if it was just THAT bike, or what, but I remember that it instilled such confidence in me, I was riding along a favourite road of mine one evening, and on going round a particular right-hander, I just knew, that on coming back the other way (with said bend now as a left-hander) I would definitely get my knee down.
Now comes the silly bit.............I approached the bend faster than I normally would have done, and simply attacked it at a pace that I thought MAY NOT be safe. The subsequent lean-angle needed to negotiate the bend (at all) saw my knee well and truly scraping the tarmac, and well.............what a feeling !! :thumbup
Absolutely made up, I was.........:biggrin
So, the crux of all this is that IMHO, you have to be prepared to exceed that lean-angle that we all have in our head, and simply lean over some more. Then you will do it. Having said that, I threw caution to the wind that evening, and I really would NOT recommend anyone else to do that.
Take care, and good luck ! :thumbup