Currently I'm running a 10/7 and I haven't leaned the engine out to see the maxium RPM's due to break-in. Compared to my Kaos 40 (running a Magnum 52, Rossi Pipe, 10/7, and flies about 112 MPH level flight) it seems faster. After a few more tank fulls I will lean it out and run it past the radar gun. Will let you know the findings.