beats me ?, thank Honda for that !..lol. I guess they want them to wear out faster ?, so you can buy more ??.lol. I replaced both sides on my '05 trx500fm, had to heat them in order to get them out !..lol. pretty much melted them, but I was replacing them anyway ?, no loss there. and the steel rod that runs the length was rusted and pitted on the ends ?, so, I replaced them. I agree, plastic rubbing on steel ?, not to smart !..lol.Why would they make those plastic. who Thought that was a good idea??