Incorrect Engine Oil, Air filter is clogged and dirt is reaching the bearing liners and journals. Oil pump failure. Clearances between journal and Crankshaft aren't enough to lubricate crank shaft.
Lack of oil & filter changes, incorrect oil, running low on oil, excessive over revving.
good lubrication and balance are paramount
If AF refers to Atrial fibrillation, yes, it can shorten your life.
Most cases produce symptoms but do not shorten life expectancy.
Some mild upgrades can actually lengthen the life. It's the major upgrades that can shorten the life.
it can shorten your life span because i am 16 and the specialist told me that i could die in my 30s because of it
Under ideal conditions....forever. Corrosion is the enemy of parts like this. If you live by the Ocean, salt air will shorten the life for instance.
No.
Most likely
factors affecting product life cycle
Yes if too much it can shorten your life
No, a magnet will not affect a battery.