Taken from Freakbikers Burrito build off Facebook page, shortened by me for relevance here:
"1. A Burrito style bike can be made from what ever you can come up with. Old cut up bike frames, exercise equipment, porch swings, your grandpa's outhouse, etc. Just about anything that you can think of to build your bike will be allowed.
2. It must be long and as low as possible. Road hazards and ground clearance are never in the formula for ride ability. The more it bottoms out or scrapes, the more successful the build is.
3. The seat must be lower than a stock 24" bike. Remember that this is not a retail store cruiser bike. Cram the seat as low as you can get it, but also make sure that you can ride the beast and be fairly comfortable.
4. This is not a chopper style bike. Long chopper style forks take away from the beauty and grace of what a true Burrito is.
5. A Burrito cannot have a real nice paint job. Anything more than a deluxe puff can jobber is too much. If it is too shinny, old ladies may pass out from the shock factor of the bike itself, along with glaring paint with sparkles.
6. The driveline must be unique. An average Joe must be able to recognize that the builder was concerned enough about his/her balls/Labia to avoid them from entanglement of the chain. The more interesting chain routes the better. Jackshafts, gears, idlers etc. Exotic drivelines are also very much accepted. Shaft, belt, friction or hydraulic would be awesome. Just make sure they actually work to propel the bike!
7. Another one of the original guidelines: "Turning radius must be a minimum of 25 feet, or just within the average two lane roadway. If not then it either doesn’t have enough rake, or the wheelbase is to short."
This also may or may not come into play. I've seen many Burritos in the last few years that have very adequate turning radius while still being long and raked out. They still don't turn as tight as a regular bike but they can easily manuever within the 25 foot minimum. Although more length or rake may equal more votes for your bike, it is not mandatory that you need a football field to be elligible for this contest.
8. The Burrito cannot have a kickstand. If it does then it is too high, or too pretty. Pure ,inncent and direct to the point!"