So I was workin on the bike, 97 ZX9R, so that I could change the leaky valve cover gasket. I finally get it off and get ready to put on the new gasket and put everything back together when I notice that 3 of the 4 air suction tubes are worn quite a bit at the top. My Haynes manual say to pull them out and check the o-rings at the bottom but I can't get them out. Is some trick I'm missing or what? Thanx for any help you can give.