The new weight rules were introduced at the start of 2008 due to Ducati’s decision to bring the larger capacity 1200cc 1098/1198 to the championship.
However, while Ducati emerged manufacturer champions in 2008 and 2009, they have struggled for pace at times in 2010 and, following a review that showed the ‘average value of event favours the 1000cc 4-cylinder’, the following steps have been taken.
“From the next SBK event at Miller Motorsports Park (USA) on 29-30-31 May, the new minimum weight for 1200cc 2-cylinder motorcycles is decreased to 165 Kg, a reduction of 3 Kg as stipulated in Article 188.8.131.52 of the FIM rulebook.
“The minimum weight for 1000cc 4-cylinder motorcycles will remain unchanged (162 Kg).”
So far this season, the average value of events has shown the 4-cylinder bikes is more than five points per round.
Source | Crash.net