cracked headtube

I recently replaced my road AL frame after I noticed a hairline crack at the front of the headtube,
starting at the top going down half way on a 58cm frame. This happened after about 7-8 years. Is
this a common occurance? Would it be caused by the angle of the stem and body weight placed on
profile bars? I would have thought that shouldn't be a factor since the stem sits inside the steerer
tube with this 1inch threaded headset config.

 

a pic would be helpful.

aluminum has no fatigue limit, so cracking after an extended period is not unusual. some frames are
better than others. either way, stop riding it!

bicyclette wrote:
> I recently replaced my road AL frame after I noticed a hairline crack at the front of the
> headtube, starting at the top going down half way on a 58cm frame. This happened after about 7-8
> years. Is this a common occurance? Would it be caused by the angle of the stem and body weight
> placed on profile bars? I would have thought that shouldn't be a factor since the stem sits inside
> the steerer tube with this 1inch threaded headset config.