The most important element in reducing jiggle in your mirrors is not about mounting, it is about the lens angle...
Many mirror manufacturers promote "realistic size" as a feature of their mirrors,.. but, it is the amount of wide angle to the lens that matters...
You know that "objects are closer than they appear" that gets pasted on some car mirrors? That is wide angle...
Motorcycle mirrors are naturally smaller than car mirrors and also, get more vibration,.. so a wider angle view is needed for two reasons...
If your mirrors are "realistic view", (read flat lens),.. they will show vibration,... no matter what...
... but, too wide angle, and you'll just see cars as dots...
They need to have just the right balance of contour to show the view needed for their size, and at the distance from you, that is needed...
So,... check them out before you buy...
Hold them at the distance they will be mounted and see what your field of view is...
You should be able to see, two or three lanes at a normal following distance, but cars should be identifiable as cars and not dots at that distance...
If you buy mirrors with this amount of view angle, they won't show vibration excessively...
This same principal, is why cameras with telephoto lenses, need a tripod to steady them, whereas wide angle cameras can be hand held...
It's all about the angle... movement is exaggerated by telephoto and reduced by wider view angles...
Motorcycles,.. being lighter than cars, transfer more engine and road vibration, and need a wider angle lens to compensate...
Apologies for the excessive verbiage,.. garbage...
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