In 2007 , MotoGP reduced the engine size to 800 cc ( 49 cu in ) .
Ducati continued to be the fastest with a bike that was markedly quicker than its rivals as was displayed by Casey Stoner on tracks with long straights .
In 2007 , MotoGP reduced the engine size to 800 cc ( 49 cu in ) , and Ducati continued to be the fastest with a bike that was markedly quicker than its rivals as was displayed by Casey Stoner on tracks with long straights .