I run the 750j/k forks in a couple of 750 slabbies'. Length wise they are fine, I run the bars under the yokes with 3- 5mm showing above the top yoke. One bike is a race bike with an 1100 motor, which I run stiffer springs in, but other wise the forks are stock.
Ground clearance is fine, and I would think for road riding the stock springs will be ok. The 1100 frame is a little shorter than the 750 frame so has more weight on the front end so you will need to go stiffer on the springs if you start any track riding.