I am quite happy with my 9-99 in my 87 inch Ziroli Stearman. At 30 pounds it gets off the ground in less than 50 feet and flies very realistically just like a full size Stearman but faster. I am getting 4900 rpm on a 24X12 Xoar prop. I get only 4300 rpm during the first minute of running but it increases after I warm it up and go back and forth from idle to WOT several times. I am using on board ignition which kicks in at about i/2 throttle. It idles great at 1700 rpm. I have followed all of Maxam's advice except for the use of the aquarium pump and the engine continues to seem very 'buttery smooth" when turned over by hand. I use 20 cc of air-tool oil and 5cc of after-run oil at the end of each flying day. I am wondering if Maxam has any additional advice regarding laying these engines up for the winter.