Does anyone know what the factory guys were able to get reliably out of a pumped up 426 engine? I am seriously thinking about 2 options for my supermoto endeavors. 1) spend considerable money with engine work to try and get over 50HP to the rear wheel and have it last a while if at all possible. 2) buy a KTM and start all over with a bigger displacement machine that has more room to grow. What I am looking for is anyone with inside info from some of the builders that have seen huge power increases with head/bore/stroke work and can share that info or point me to a builder that can make it happen. I have read the TT supermoto project bike page and noticed that they got 49+ hp with a big bore/carb/ignition upgrade, I am actually looking for more than that. i plan on competing in the AMA supermoto races thsi year and would like to run my 426 since all of the other trick stuff is already done (susp, brakes,wheels etc.) wheres the super duper secret stuff kept?