Bridgestone – Bridgestone Tire Tubes - 10-17 in. Rim, including TR4 tubes in 60/100-12 and 60/100-14, 70/100-17 and 90/100-14 minicycle sizes, 250A/70/100-10 small-wheel fitments, 325/350-16 street sizes and PV78 140/150/90-15 scooter tubes, is the small-diameter half of the tube range. Wheels in this bracket belong to youth motocross bikes, pit bikes, trail minis, scooters and 15 and 16 inch cruiser rears, and each one has its own demands. A mini rider needs a tube that survives low pressures and hard landings without pinching at the rim; a scooter or cruiser rear needs a stem angle and wall thickness that hold pressure through thousands of low-speed miles. Bridgestone's TR4 heavy duty construction gives the first group a thicker, more puncture-resistant wall, while PV78 fitments handle scooter applications. Matching the tube to the actual tire section is what keeps the wall from stretching thin, so check the marked size range before ordering rather than assuming a close fit will do. It also pays to install a fresh rim strip alongside a new tube, since a hardened or shifted strip is a common cause of mysterious slow leaks.