The kick-starter idler gear comes with a bronze bushing that rides on the transmission countershaft. When the bushing wears out, it allows the idler gear to cock sideways enough to break the snap ring out of the countershaft. This not only ruins the countershaft, but the broken parts are now floating around in the transmission. If the snap ring goes between two gears, you can just imagine the resulting damage. So a steel bushing was installed to replace the stock bronze one, which solves the problem.