on a customers bike I do the basic trick of a spoke ruleron the drop and bottom of thever resting on it.
on my bikes I put one where it feels comfortable then use the yardstick method with a small level.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk