Above chart shows the Horsepower ratings for our old 780cc kit vs.
an early 725 kit vs. an uncorked 650 motor.
Above chart shows the Torque ratings for our old 780cc kit vs. an
early 725 kit vs. an uncorked 650 motor.
*This 'stock vs.725 vs.780' dyno chart really should only be looked at as a 'general information' comparison. These graphs were made with 3 different motorcycles and done several years apart. The individual runs were pulled from our archive of hundreds of dyno runs and selected to fit together in one graphic and be good representations of 3 different builds. The intent is to show some examples of what is possible and how much stronger the 780 is over the 725. Again, this chart should be looked at as a COMPARISON not as some sort of 'this is exactly what you will get' documentation. We probably should erase all the numbers out of it but that would probably raise as many questions as leaving the numbers in.
When you start building a motor beyond stock there are so many variables that no two people are going to create the same dyno curve. There are small details that have significant impacts. Someone who just bolts in a big bore kit will have a very strong running motor and be perfectly happy. Another builder who does a nice 5-angle valve job, cleans up the ports, dials in the squish clearance and tunes the jetting on a dyno will have a stronger motor with a better HP curve even though it used the exact same parts.*