Burnt Exhaust Valves-How Prevalent?

[bmw633]

Hi,

After my GZ250 grenaded itself with a broken-off exhaust valve, I have noticed that others have had problems with their exhaust valves, also. How common is this problem?

Someone contacted me about selling their bike with burnt exhaust valves, after 10,000 miles on the odometer, like my bike. Could this be a manufacturer defect caused by a too lean condition in the carburetor?

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