I have one on my build, my tire is a spare from a '94 Chrysler Lebaron. I forgot what was the problem I had, but something was hard to get to find the radii and the spacing of the bolts. If you have a an axle from the car or have all the measurements of the axle u will be able to make the hub run true.
I didnt have all the measurements, so I found the center of the bolt holes and used that to find the center of the hub, I used those measurements to make a pattern disc and with careful marking and re checking I made the hub disc. You will most likely need a 6x6 plate about 3/8" thick for the flange. having a lathe with some balls is a big help for this, or a lot of work is in store for this. I had to make a 6" disc by roughing the square plate to a roundish shape with a vert band saw, then I had to true the disc on the lathe.
Once the center hole is drilled, the whole thing will reference off of that hole, this is why the measurements are key to have and to make sure the part is laid out right before u drill anything. I had bought a hub for sprockets but would fit the flange, I machined the disc to fit, checked the tire rim and then drilled bolt holes, it worked out good. After that I set up the hub assembly to weld. Having a good welder helps and skill to do this aswell.
I managed to get all this done and having about less 1/8" runout, in the end this is also very critical if you want a smother ride, with out too many other possible problems associated with vibration wrecking the bike apart.
This is my bike on this thread here...
http://www.diygokarts.com/vb/showthread.php?t=5461
