I have a 2005 gixxa1000 and my 2mates have 2006 models that do the same thing except if you try to launch them hard enough when it makes this noise my clutch will actually lock up and send the nose cone skyward very quickly.Suzuki Australia have recognised this problem and are trialling 750 clutch springs and the washer at the back of the clutch basket needs 4 slots cut in it from the inner radius to the outer radius to let more oil to flow to the clutch.my bike is getting done this thursday 10.8.06 so will let you know what happens.Also on my service they adjusted the Back Torque Limiter (B.T.L)back to original spec which did seem to help but did not fix the problem.If you have any info as well let me know,much appreciated.