I need to start carrying a tube to fit a 700×23 with me. Seems like most of the time I offer to help, the rider says they’re waiting for someone to pick them up, or like this morning the nice young lady on the Custis walking down the Rosslyn hill on her way to Foggy Bottom who said she’d just walk. Can someone tell me what size nut is usually on a non-quick release hub so I can have the right wrench with me too?