I have an 04 RoadKing with the Harley lowering air shocks. I also used a lowering kit to bring it down another 1" or so.
My question is will this cause the fender to come in contact with the tire under some conditions. I seem to have eneough clearance, However,I do feel bottoming out on the shocks under certain conditions ie manhole covers if deep.I have not ridden with a passenger as of yet. BTW, the bike handles pretty good lowered looks great.

 

Gotta think those great looks are gonna get you hurt at some point. I lowered a Road King several years ago then spent the summer dragging floorboards & exhaust. At some point, and it sounds like you have reached it, the bike is to low and the frame, kick stand, foot board, or some other part is gonna catch on something that doesn't move & you'll get tossed off when the bike rotates.

 

I added a lowering kit to the rear of my bike, but I thought it also said not to mix it with lowered shocks 'cause that would be too low. If I were youI'd probably remove one or the other to be safe, but that's just me.I definitely would never ride two up in your configuration.

 

At 9.5" the tire will contact the fender. Profile shocks are 12". Forget the math and get a quality air-ride system.

 

Had a 2 1\4" Rear Lowering Cams & Ft lowered 1 1\4" Progressive... Riding Solo still had to pump the rear air shocks up way high to not bottom out and larger dips - 2-up forget it & lost the cush for the tush ride...
Moved it up to a rear 1 1\4" drop - much better - better overall ride and even 2-up it takes a biggie dip to hit the tire - I ended up going to Progressive 440's in the rear 11 1\2" and looking now into a better Rear Air Ride System...

 

ride 2-up then test ride and adjust to a safe height.

 

There are bolts, wiring harnesses, and all kinds of other chit under the rear fender that you do NOT want your tire contacting. Unless you need the bike lowered that far because you are vertically challenged, you are flirting with disaster. Grind the wiring harnessa few times and you'll find out quickly. I would never ever lower a bike more than 1 inch, and there are work arounds for that. If you are short, get a good air ride suspension, like Legends, Platinum, etc...this will allow you to lower the bike for parking, walking it around, looking cool, etc, but allow raising up to a safe, comfrotable height when actually riding. HD suspension is terrible anyway...when you lower it, you've just used up 1 of the 3 inches of bad suspension. If you must lower the bike an inch, put a decent suspension under it, and nothing HD offers can be called decent. It will cost you money, but will be the best money you spend on the bike in the long run. Traxxion Dynamics AK20 cartridges in the front end...they will set them up an inch lower and you will have something on the bike like you've never experienced on any HD. They also offer Bitubo rear shocks in a 300mm (one inch lower) which are adjustable for rebound, preload, and compression. Best money you'll ever spend...

 

Just my .02. I put the 1 1/4 lowering cam on my 07 Ulta and while riding 2 up I don't bottom out. I'm going to send my seat to Mean City Cycles when the season is over and have em drop it 1 to1 1/2 inches and put inmemory foam.