This is the socket you need if you are trying to install a new clutch, or you want to remove your old one on your GY6 (QMB139, QMI152, & QMJ157). A lot of people don't have a socket this big, and it’s difficult to find at your local auto parts store. This is 39mm on one side, and 41mm on the other. This works on almost all clutch pulleys, but definitely check the size before ordering. If it’s a GY6, it definitely will work.
