I bought a 2007 yz450f yesterday and it wasn't running quite right. So I pulled the carb off and it's not like the carbs I've dealt with in the past. When I picked it up it was a huge pain to start and had zero idle. It would run just fine when I kept my hand on the gas to create an idle though. I turned the idle screw up just a touch and it'll start and idle just fine, first kick when it's cold. So I decided I was going to start by cleaning the carb, most of it looked clean and perfect until I pulled the slider cover. There was some gunk all around in there. When I pulled the slider out this little plate thing fell out with it. Looks like that rubber part wont sit correctly. Could that be a thing? Do I replace the rubber ring or the whole little plate thing?