RE: fpe 5.8 with the shakes...
rc ..... comparing a twin to a single and then talking about vibration hurting the twin.....
kinda like comparing apples to oranges...... secondly because the vibration is the WORST at around 2600or so .... the solid mount and the increased intensity of say "full throttle" could be masking vibration that is still present but not perceptible to the eye or ear and could possibly still be of enough intensity to wipe out the bearings.
but hay dont take my word for it ..... mount up a single to the old steel test stand and try it....... the proof is in the puddin.