Rolling objects hazard

I was riding up a main drag in town the other day
when I heard a loud BANG behind me at an intersection
with traffic lights. Looking in the mirror I saw
an SUV with a shredded rear body pulling over to
the curb... but something had broken off and was
rolling right across the road.

If I'd been riding the other direction I might have
been at risk of colliding with this runaway piece
of debris.

So on top of all the other potential hazards, I have to
continually compute a few more what-ifs (what if that
women in the Jeep Cherokee runs that yellow light and
collides with that yahoo in the Bronco then [computing
quick estimate of vector forces] her spare tire might
come loose and come rolling in my direction...)

Sean_Q_

Many years, in West Africa, I was riding about 30 yards behind my
wife's bike. A cocoa lorry (think 5 ton stakebed with a tarp over the
load) passed me. His spare tire, which had been laying on top of the
tarp slipped off and landed in the road in front of me, then bounced
off to the right. 2 seconds earlier, and I would have been dead. 2
seconds later, and she would have. I still shiver.

Oh, and before you chide me for riding slower than a cocoa lorry...we
were on Peace Corps issue mopeds at the time.

Steve