I actually do also have the RAM-HOL-UN10BU, and you're right, it does fit perfectly with the S8 in all 4 corners. I was using it for a Garmin Nuvi on my other bike which worked great. I did try it on my S8 but I find the tension isn't strong enough (because the S8 is too narrow) and with a simple shake test with my hand, the phone easily slips out. I'm not confident it will secure my phone in place like my smaller x-grip (RAM-HOL-UN7BU).

 

It's been working perfectly with my s8 the past couple of years.

 

I am using the Kuryakyn Premium Handlebar Accessory Mount p/n 1677 with the Clutch Perch Mount p/n 1677. It will hold my phone or Garmin.

 

When I got my '11 ultra, it has Harley's GPS mount already installed on the inner fairing, but no GPS. I like using my phone for music and nav, so I modified a phone case by adding a GPS weather cover to it. Phone snaps on and off the GPS mount.

Initially was going to get deeper into it and run power to the phone from the GPS mount, but still running power from lighter adapter in fairing right now.

Without already having the GPS fairing mount, this world be very pricey for what it accomplishes.

Here's my build thread.

https://www.hdforums.com/forum/touri...l#post15230627

 

I’ve been using the Kuryakyn tech-mount with handlebar clamp and have enjoyed it. No issues over the last couple years.

 

GPS is on RAM mounts. iPod I clipped to windshield bags. XM radio is mounted to homemade bracket riveted to bag mounts.

 

RAM Mounts are the way to go. There’s many different mounting options. On my RK i hated it mounted to the bars so I mounted one to the Console with a 45deg mount. On my Ultra I have one mounted to the bars with lower profile mount.

 

I like the Quadlock better than the RAM X grip.
Very tight and secure. Also low profile:

 

After seeing your Road King, I just ordered the Quadlock with the same setup

 

To do the same you need one extra spacer and one extra arm. (other than the mount the the phone case)