Had a weird oscillation in the rear of the tandem yesterday in the middle the ride. Pulled over and saw a strange bulge in the tire. Removed it today and it appears the casing split. First set of Schwalbe Ones after using Conti 4 seasons for years without an issue and this was about our 4th or 5th ride. However - the Schwalbe's are a much better riding and handling tire. Hopefully won't have a problem getting a return.