Originally Posted by
CACycling
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Instead, I use the mirror until I see the break I need then I do a quick head check to make sure I didn't miss anything and go.
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That's pretty much the way I use a mirror too.
A Motorcycle Safety Foundation instructor here described a mirror as having a one word vocabulary. It can only say "No". If the road behind looks clear in the mirror, you still need to turn your head and do a visual check before changing lanes.