Originally Posted by Maximo

did you change the OWB shaft when you changed the OWB ? the shaft is actually softer then the bearings, so if the OWb has worn out so has the shaft...replacing the OWB without replacing the shaft will result in slipping right away......When a OWB starts to slip you need to stop imediately and flush the engine with WD40..If you continue to try to start it with a slipping OWB you are just wearing out the shaft and bearings, as soon as its slipping its causing damage....some fuels oil package causes OWB's to slip very easily, some fuels work awesome with OWB, others can be a nightmare...... WD40 will degum the OWB instantly, you just need to give it about 10 minute to evaporate out of the engine before you run... Everything your describing sounds like typical OWB behavior, which is why I much prefer a bump box..... Plus the OWB shaft/backplate bushing can cause a huge air leak and make tuning difficult...