Here are a few pictures of my motorcycle tire changing setup. It's a very simple setup and the parts to build it are relatively inexpensive. I used one 2' section of 5/8" threaded rod that you can purchase at Lowe's. I turned down the top 8" of threads on my hobby lathe so I wouldn't have to turn the wing nut so far before it made contact with the motorcycle tire rim. You could also use a grinder. You need to leave at least 6" of thread above the top of the 13" car rim. 6" of thread should be more then enough to lock down most any motorcycle tire.
Here is a close up of the simple wing nut I welded up. This speeds up the mounting and removal of your motorcycle tire. Without removing the top 8" of threads on the threaded rod its a LONG way to turn that nut down to lock the tire on the rim. You DO need the extra length though as a pivot/leverage point for the tire tool. I tie rapped some of that nylon reinforced flexible rubber hose to protect my motorcycle tire rims from scratches. The rubber hose also helps keep the motorcycle rim from slipping when your mounting and de-mounting your tire. Note that I welded a 3/4" ID washer in the center of the car rim. This keeps the car rim centered and makes a sturdy place to torque the car rim to the 2"x6" treated lumber that I have C clamped to my picnic table. You can mount this setup to almost any thing your mind can imagine, a work bench, custom welded floor mount, motorcycle trailer, trailer hitch, work bench and lastly the kitchen table although the wife might not prefer you do so.
I use a piece of PVC pipe on the exposed metal rod to help protect the shiny finish on my no-scufftiretool and to protect the threads on the threaded rod. The PVC pipe covers the part of the rod that I removed the threads from and any left over threads after you lock the tire down. You can also see a small piece of 1/4" luan plywood under the flat metal stock. The wood protects the finish on the motorcycle tire rim when I torque it down to the car rim. After the wing nut is torqued down it becomes very stable so you can lever your tire tool around it easily.
I ended up cutting the top outer lip of the car rim off with a saws all and then tacking two runs of 1/4" round stock to the top of the rim. I wanted a nice flat surface for the rubber tubing to rest on and I wanted ample clearance so my brake rotors wouldn't touch the bottom of the car rim. My Valkyrie came just a bit to close for my liking. Doing this also gave me a little more play to move the motorcycle rim around a bit, and get it centered correctly. I just used what I had.
Notice the 1/2" rod that is welded on the top and bottom of the left side of the rim. The top rod that you see in the picture keeps the motorcycle rim from spinning on the car rim, and the bottom rod keeps the car rim from spinning on the 2x6. The only thing I didn't show is a 1/2" ID piece of transmission rubber hose that fits over top metal rod to protect your motorcycle rim. When you mount your motorcycle rim on the car rim make sure to butt one of the spokes up against the rubber protected metal rod. All of these tire tools available (No-scuff, No-Mar, Wikco, MoJo etc..) require the user to apply either a clockwise or counter clock wise motion to demount and or mount a tire on a motorcycle rim. If you find one that doesn't please email me because I want to see it. One of the problems with the Harbor Freight tire changer is it has a tendency to let the rim spin when leverage is applied during the mount and demount process. A spinning rim is either going scratch your rims or make you cuss, probably both.