A Sutur clutch is a true slipper clutch designed especially for road race application in this case . It allows you to approach a corner hot , smash down the gears to a suitable desired entry speed all the while the rear tire is able to avoid locking up / skidding , if excessive speed for that gear selected . Sutur make the absolute best top shelf components , World Superbike swingarm for R1 I think I recall around 10k AU . If you want to roadrace like AC41 , then it is the best investment .
The stock Busa has a semi slip clutch , it helps the rear slip and not lock on a mistaken low gear selection . Have you ever taken off on you Busa from standing start , only to have it hop and jump on take off , instead of smoothly , when trying to leave fast ? Well , you can get a Brocks / APE etc. center ring to help eliminate that hop on launch , and if you tune your Busa with pipe install , you can get extra hd springs while you there . Some riders can launch their Busa with the stock oem setup just fine , as is . I do know I had certain times where I got beaten off the line because the Busa was hopping before I got that ring done .