Hey I've got 2 of them that friends took them off there trainer's and handed them over to me since they wanted an O.S. ,but as it turn's out I eliminated all the blue safe lock collars and also eliminated the (20 lbs.) fly wheel added a tower muffler 15% cool power & with a MA 10x7, I tach. it @ 14.700 RPM. it really flies my R/C Nobler just great even though I should have changed the wood that forms the fuse it's nice hard wood but it's also heavy.But my Nobler has crashed a few time's already but repairable since the wood is so dame heard.[>:]