My first rebuild since I was a teenager; 77 XS, I have removed the valve springs, trying to push the valve out and it sticks in the guide as soon as it goes past the seal. The end of the stem feels like it has a very slight lip on it. I know I could push it through with a light hammer, but before that, is it usual for the valve to hang up like that? If I push it out with a bit of force, am I going to scratch the inside of the guide? My solution is to use some emery cloth on it to clear off the burr, but that will take some time. Search had nothing on point.