Did a test this morning to evaluate engine vibration. Used was an Evolution 13x6 prop yet unbalanced. It had a distinctly heavy end, which was marked. The heavy end was tested in four mounting positions, tdc, bdc, and 90° before and after tdc with no observable vibration differences. It was removed and replaced with a balanced prop and notably less vibration.

Conclusion: The unbalanced prop did not counter any inherent engine unbalance suggesting there is none and that vibration of the 10GX is due to other factors not associated with balance.