Okay, this is probably a really dumb question because I have never done this before...but I was trying to install piston rings today on my Yamaha DT80 and a few things happened: First off, The two new rings I got were not the same (one was greenish and slightly rough and one was metallic). What is the difference? Does it matter where they go? Secondly, I tried to install the cylinder over the piston and it cracked both rings because they *seemed* to be too large, even though my rings were standard size. Any suggestions? These were OEM rings. Thanks!