Some clutches were built under license from Polaris, and referred to as the HP clutch. Ski-Doo encountered many problems with some of these clutches. Some were prone to vibration failure and were recalled ** Ski-Doo and replaced with a Roller Square Shaft unit. There is a ski doo discussion forum where you can ask specific questions at:
http://www.hardcoresledder.com/forumsOr try asking a more specific question under ***** answers/transportation/boats and boating/ or the maintenance section.Good luck.