^^Also try inflating the tube and pull to stretch the tube in small sections which may enlarge the hole enough to hear or feel a leak. Hold the tube very close to your nose as it is very sensitive and can feel very small areas of escaping air and there may be a difference in smell. This is main reason why I stopped using latex years ago. Got tired of spending 30+ minutes to find and patch a hole. Plenty of lightweight butyl tubes out there that are as light and ride the same as latex.