I took my bike into two different shops telling them that I felt the handlebar and stem was misaligned with the front wheel. Both shops disagreed with me and said it was fine. They said if it was misaligned it was imperceptible. I ignored "the problem" for six more months and then I had a friend take look at it. He wondered how I could even enjoy riding with it so misaligned. It took him a whole three minutes to fix it.
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Two wheels good. Four wheels bad.