I had the imfamous clutch "chatter" problem when trying to launch my busa. nothing short of replacing the entire large outter basket fixed ths problem. At the time, people thought it could be an oiling problem (the clutch plates were getting dried out), so they drilled more holes in the basket, and then moved on to cutting groves in the pusher. I started with 1 grove, then moved to 4, 1 every 90 degrees.
Bottom line was that it didn't help the chatter problem, and i personally ended up spinning a bearing in my motor. I cant say it was directly caused by the pusher mod, because oil going to the pusher is controlled by a jet in the oil pump distributer, so it can only get as much oil as that jet allowed no matter how many grooves were cut in the pusher.
_and it was a 1363 with a lot of passes on it! so who knows.
bottom line is that the BDE clutch cushion fixes the problem (unfortunately it wasnt out when i sold my busa), so it was nothing to do with oil.
my gsxr 1000 started chattering also after a few dozen passes, and the BDE clutch cushion fixed.that to-