We have been extensively testing exhausts and other products on our 2010 SG and can note a few details. As expected, the EFI is very lean thru the entire cruise range. The AFR target is 14.6:1 when in closed loop and the logging we have done with a wideband has shown a measured AFR of 14.5-15.0:1. While this closed loop strategy has not changed from previous models, issues come into play from a heat standpoint not only from the engine but from the catalyst. The testing we have done does not show a significant loss of power with the catalyst in place as we are getting pretty good Hp/Tq #s, however the catalyst has a dramatic parasitic effect as exhaust temps increase and it dissipates heat. A strategy the Motor Company uses to prevent problems is to then overly fuel the transition area which on the 2010 bike is overly rich. We have seen very good improvements in cooling, throttle response, and performance with tuning our stock bike to correct the AFR and igntion timing, and have seen even better results by changing the air cleaner and muffler and EFI tuning. I did some direct comparisons on the dyno this week with the stock EFI on the stock bike, with the PC-V tuned on stock bike, stock EFI and Jackpot PowerTube muffler, as well as the Stage 1 air cleaner PowerTube muffler and PC-V, all of these done on the same bike, same day, same dyno. I will try to get the charts posted here tomorrow.