Sad.
I've simply bent back to straight similar bars on a couple of my bikes.
Seems reasonable.
Once the metal has yielded, they never have the same strength. May be OK for a rider but definitely weaker.
Implying weaker is dangerous? Instilling fear for the novice?
"Weaker" measured in what units and at what magnitude? And what units are actually required for adequate service life?
Metal flex or yield is a way of life. Metal is used for springs which yield to absorb shock and bend routinely. In fact, every metal airplane experiences flex routinely. Replace those after the first bend?
Bending metal beyond distortion limits "work hardens it" and actually makes it slightly stiffer. If it doesn't crack, it's fine for street driving. Bend it too many times, it's a throw away due to cracking. Try it with a paper clip. It still functions as required with repeated bending until it breaks.
Gotta say, I've bent back handlebars more times than I've liked due to mishaps. Haven't had one in service fail to respond to control inputs, yet. But, I don't do motocross. And, I don't like throwing money away needlessly. I had to work too hard for it.
By all means, be as much of an ideal consumer as you wish. Replace useful items with a variant of a useful item. It's your money. At least it was.
Oh, I'm such a rebel these days.
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Carry on...