Some of the rims in the department store bikes come from Indonesia or China...where there is one particular rim manufacturer that makes rims so cheap the following two things are common:
1. CNC that is so "stringy" that you can literally "peel" off a 2-3 foot long piece of "aluminum wire". That ends up in your brake pads...
2. Centerline thickness so thin that just the act of applying final tensioning to the wheels results in premature bulging and warping at the spoke holes.
=8-)
Bottom line is - you get what you pay for...
=8-)
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5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life