Knowing what to pack for a motorcycle trip is the easy part. Actually getting all that stuff packed safety and securely while still leaving room for you to operate the bike is a different story altogether. Some of the differences from packing a car include things like weight distribution, limited space, keeping necessary items where they are easy to get to, and many others.
This How To is based on a single rider. If you have a passenger riding with you, it will require much more planning and trimming down of the non-essentials. It may even require saddlebags, or perhaps a motorcycle trailer (if your motorcycle is big enough to tow it).
Remember: Packing a motorcycle for a trip, especially a long one where you need more stuff, is not an easy task. It takes planning and preparation. It also requires you to consider taking items that are not really needed. In a car. If you think you might need it, you go ahead and throw it in the trunk and don't think twice about it. If you did that with a motorcycle, you'd need a trailer to carry everything.