https://www.titleist.com/teamtitleist/team-titleist/f/club-fitting/20143/question-about-my-driver-specs Hi, I just played a bit with a TrackMan today, and the result was a bit &amp;quot;eye opening&amp;quot;. First I tried the Shaft Optimizer with my 6 iron and it suggested Dynamic Gold X100 which I&amp;#39;m playing already, so that was okay. But then I went to the driver. I haveen-USTelligent Community 10https://www.titleist.com/teamtitleist/thread/88658?ContentTypeID=1Wed, 27 Feb 2013 18:28:39 GMT9ab519fc-5311-4952-85cd-0a0ceffb73fb:8d91ca37-77c2-4723-991d-db98ac4a632fDon O<p>The vendor&#39;s rating of R, S, X is only a guide.&nbsp; There are no standards.&nbsp; Most other drivers have a stock 45.75 inch shaft.&nbsp; Just as an example, I gained yardage hitting into a net with a Trackman just switching between R shafts Bassara 50 g to the Blue shaft 62 g on a 913 D2.&nbsp; This was due to smash factor from 1.4 to 1.5 and a lower spin.&nbsp; Obviously, your results will vary.&nbsp; I&#39;d let a fitter work with my swing and optimize launch and trajectory without deciding on weight and flex before starting the process.&nbsp; I think your only conclusion now is your current shaft may not be optimal.</p><div style="clear:both;"></div>https://www.titleist.com/teamtitleist/thread/88651?ContentTypeID=1Wed, 27 Feb 2013 17:03:51 GMT9ab519fc-5311-4952-85cd-0a0ceffb73fb:3a958320-63ae-4971-84a0-2513cdb0296asteve b<p>Chris - you ask some good questions here. I have that KK driver in some of my fitting carts. let me get some specs and compare it for you and I will get back to you soon.</p> <p>steve ball</p><div style="clear:both;"></div>