From the "How to eliminate the 'Bog'" stickie.... ......or you can oring the link. The replacement spring is a one time deal, the oring, needs to be replaced from time to time. To install the spring, you really have to pull the carb. The oring, can easily be installed on the bike. Orings cost about $.20 each (#78 in the plumbing section at Lowes)........ I'm assuming between the arm and spring, correct?