JohnThat is an unusual rig. If it doesn't work well for you try a No-Mar machine. Not cheap, but well designed. I use a manual Coates machine I picked up used. I do use the No-Mar bead breaker attachment for the Coates so I don't scratch rims, and for some wheels with a very shallow dish I use the No-Mar bar instead of the Coates bar.
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The No Mar was on my list along with the Rabaconda$$ but stumbled across this set up and the u-tube videos were impressive and most of all it seemed a lot more portable than the NoMar so I can just throw it in the truck when I do trailer the bike somewhere being my bikes seem to attract every nail on the highway. I let you all know how it works this weekend