Original sentence: In 2003 Buell introduced a whole new engine so efficient it passed emmision tests well into 2006.Two of the notable innovations are the use of the hollow frame as a gas tank and the hollow rear swing-arm to hold the engine oil.What makes Buells stand apart from their Harley-Davidson origins are what Buell refers to as the "Trilogy of Tech": mass centralization, low unstrung weight, and frame rigidity
Edited sentence: In 2003 Buell introduced a whole new engine so efficient it passed emmision teste well into 2006.Mass centralization, low unstrung weight and frame rigidity.The most notable innovations are the use of the frame to double as a gas tank and the rear swing-arm to hold the engine oil.What makes Buell's stand apart from their Harley-Davidson origins are their innovative design features the "Trilogy of Tech"