You need to look harder for bubbles... some times TINY little holes can be the cause and they are missed on a normal sweep. Could also be the valve. Are they light race tubes - they will lose a lot more air than normal rubber tubes.
@hippy started
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You need to look harder for bubbles... some times TINY little holes can be the cause and they are missed on a normal sweep. Could also be the valve. Are they light race tubes - they will lose a lot more air than normal rubber tubes.