They don't coat the inside of your tubes. If any powder coat does get inside the seat tube it won't be thick enough to warrant changing a seatpost size and you can always use wet and dry paper to remove excess layers.
@roboto started
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They don't coat the inside of your tubes. If any powder coat does get inside the seat tube it won't be thick enough to warrant changing a seatpost size and you can always use wet and dry paper to remove excess layers.