I originally posted this as a response to another conversation in the North American forum, but thought the information might be of use to people who are reading this forum.
Below you will find the complete text of the IATA Dangerous Goods Regulations (DGR) that govern shipping motorcycles by air.
The moto itself is classified under UN 3166 as a 'Vehicle, Flammable Liquid Powered'. The Packing Instruction that gives the details of how the vehicle must be packed so that it is accepted for shipment is Packing Instruction 900.
The first image below shows the rules for UN 3166, the second illustration shows the rules for Packing Instruction 900. The two go hand in hand, in other words, if you comply with the packing instruction, you can submit your moto for shipment under UN 3166.
Some points that your cargo acceptance agent (the airline employee) may not be aware of:
If it is impossible (very unlikely) for the moto to be loaded in any position other than right-side up, then you don't have to drain all the fuel. Just run the tank down as low as possible, in no case have more than a quarter of a tank of fuel in it. On the other hand, if your moto is packed in a rectangular crate, and it is possible that some stupid person could put the crate in the airplane upside down, then you have to drain every drop of fuel from every nook and cranny of the moto - tank, carbs, etc.
If the battery is secured in its original location on the moto (where the manufacturer put it), and if all the panels are in place securing and protecting the battery, then you don't have to remove it, nor do you have to disconnect it.
The battery has to comply with the referenced packing instruction for batteries, however, just about every motorcycle or car battery made in the last 30 years will comply. That packing instruction says, more or less, that the battery must not melt like a chocolate bar and spill electrolyte all over if the ambient temperature gets up to 55 degrees C.
If it is obvious to an average person that the package you are shipping is, in fact, a motorcycle, then you do not have to put a sticker on it. If it is enclosed inside a box or crate - such that no-one could tell that there is a motorcycle inside the box or crate - then you need a class 9 (misc) DG sticker.
Hope this information is useful to you.
UN 3166 DGR Rules (Vehicles, Flammable Liquid Powered)
Packing Instruction 900 - how to pack a moto for air freight shipment
IMPORTANT:Note the 'State Variations' filed by the USA at the top (USG 12 and 13), and the 'Operator Variations' filed by a few carriers such as KE, MX, etc.
Example of when you don't have to drain the fuel totally, and don't need a sticker to identify the thing
It would be pretty hard to load this anyway except right side up, or fail to recognize that it is a motorcycle.