Yeesh, should have flushed the cases before I put it back together. I spent about about 2 hours trying to get the bike to clear out. It started and ran fine initially. I rode it around for a while and never really got on it to break things in a little. As soon as I got on it, the thing shut down. After that, I would pull the plug, clean it, it would start, and as soon as I revved it up, it shut down. Cleaned the plug and repeated about 50 times. After a while I got it to run long enough to go about 100 yards and then it shut down. Every time I opened up the throttle, the plug would foul and there was no bringing it back. The oil was obviously old gear case oil, the premix has a red color to it. Eventually, I started the bike and was able to keep it running at a high idle and slowly rolled on the throttle until it started to foul the plug and backed off. I kept doing this until I was able to hold it full throttle, you should have seen the cloud of smoke this thing was making. I made a full throttle run from a stop to top speed and now the bike runs absolutely perfectly. I really hated to do that on a freshly rebuilt motor, but there was no other way to keep it running.