So what are the bars made off? Lighweight racing quality aluminium and they could have been made wrong or you are just too rough with them. Ordinary alumium and the only way you can break them is with a hacksaw.
BUT C.F.-- Can break at any time after a hard knock. Could have happened before you got the bike- but the knock need not be that severe.
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How long was I in the army? Five foot seven.
Spike Milligan