James M. Lewis
Armed Forces
bigone5500, sounds like a complete rebuild in everything. Take apart the whole copter and inspect all pieces that make up the bird. Hopefully you can get more tech information from Horizon Hobby. The library link Tony has put together has a wealth of information available. The early 400/450s were breaking new ground and trying to play catch up with the European /Asian models that were tried and proven. Just reading and learning from other RC helicopter pilots has been very educational to me.