I gave up and poured 3 oz of beads into it and put the wheel assembly back together and back on my Spyder. Haven't road tested it just yet but soon.

Places I was told could balance a Spyder rear wheel but in fact could or would not (when I took it to them):

Powersports of Conroe (balance machine is broken and no ETA when it might be repaired)
Walmart Automotive (shaft to big for center of wheel)
Discount Tire (shaft too big for center of wheel)
Harley Davidson of Kingwood (said their machine could do it, but won't because its not off a Harley Davidson motorcycle)
Mancuso North (actually they said they don't have a balance machine at all, that they only use tire beads)
and The Cycle Shack of Conroe (shaft too big for center of wheel, again)

Well this was tonnes of fun! I would never have guessed it when I went to change my rear tire. I did ask if removing the bearing in the center would help, but was told no the center of the wheel would still be too small.

fyi: Using the axle shaft on jackstands technique, this Kendra tire balances perfectly just like your car tires. However I suspect this technique doesn't allow for much precision hence I went ahead and added tire beads to it anyways.

Regards and safe riding ya'll!

- Michael