Haha, I don't know about the best stirfry in Kunming, but I can say that the Laos border is very relaxed. You should certainly be able to purchase a visa on-arrival at the border.
I've been to laos before, but this time I had no intentions of doing any traveling so I simply crossed the chinese border. Walked around for about 20 minutes without buying the Lao visa and then walked back through the other side of the Chinese border crossing. The Immigrations Officer hardly glanced at my old Laos visa, he was more concerned about me exciting China on the last possible day of my Multi entry visa (he had to count the days on his fingers). I was waved right through and hung out in Xishuangbanna for a couple days before returning to Kunming.
I'm not sure about getting your bike through the border but seeing that it's very relaxed i'm assuming it would not be a big deal, and if you can get it out of China I'm sure you won't have a problem in Laos. It's simple to get the visa on the Laos border (they sell Visa's out of a shack right now, although they are working on a new Immigration building). I can't remember if they take RMB so I would be sure to bring along at least 50 dollars. If I remember correctly the most expensive Visa is for Canadians at a little over $40.
Hope that helps and be assured that there is plenty of good stirfry in KM haha. The name is actually an old nickname from back home.