DD has a Puky balance bike. We've had it for about 2 years, absolutely love it! DD rides it daily. The last few months we've had to inflate the tires about once a week. Prior to that I don't think we inflated them more than a few times since we bought the bike. We just inflated them last week and one is almost flat. We don't have an air pump, really need to get one, so I've been taking the bike to an auto shop close to our house and have them inflate it. Because the air valve is so small it sometimes takes them a few tries to get air in the tires. Anyway, all this explanation is because I'm not sure if there is a hole in the tube or if something happened when I let the guys at the auto shop air up the tires. Once a worker took the whole valve off because air wasn't getting in the tire so he thought the valve had to come off. This obviously completed deflated the tire and he had a really hard time getting it aired up after that. Those that have this bike, do you have your own air pump? If so what kind? Did you have to buy a special valve to air up the tires? Has anyone ever had to replace the tubes? Where do I buy them from? I originally bought the bike from glider rider but I think they are selling a different balance bike now.