Motorcycle camping is very subjective. Not that many years ago, my idea of camping gear for myself was a 4x8 canvas tarp, and tools rolled up in that, strapped to the risers. Now, I do like my comforts. And so does my wife, which is an important component to a good trip.
 
Some basics that you should consider:

Accommodations:

• If you do not have saddle bags, a cheap set of throw overs is worth the investment.
• A tent. The dome tents do not tend to last long unless you get into the more expensive ones. Cheap dome tents are compact and light weight.  I would avoid the really small tents, and the traditional pup tents. The reason is staying dry. If the tent is too small, you will always be against the side, and you will wake up wet.
• A rain fly is also nice to have. Even if it doesn't rain, it will help keep the dew off the tent sides.
• Sleeping bags. Go cheap, and go light. K-Mart bags work great. Unless you are camping in extreme conditions, you do not need expensive bags.
  

Cooking:

• I would recommend two pans. A cast iron fry pan, and a small sauce pan. You can eat well with these two. It is possible to cook with no pans, but much more effort, so unless you really want to rough it, I would make room for the pans. The blue speckle coated pan, plate and cup sets are nice, and not very expensive. You can buy the set, and just bring what you need. They will last for years.
• A regular fork spoon and knife wrapped in a wash cloth are far better than the camping sets that are available.
• A decent folding knife is sufficient for basic cooking.
• While most established camp sites have BBQ's and wood available, I recommend a portable propane stove. It is faster, and easier. I like to have the fire for pleasure, and the stove to cook. Plus, I hate having to get the fire going before I have my morning coffee. There are a number of very compact propane stoves out there. There are smaller butane as well, but I personally do not like them as well. The small propane Cylinders usually last us 5-7 days.
• Don't forget some basic spices and condiments. You can buy salt, pepper, and sugar packets at most supermarkets. These are much more convenient to carry. Zip locks work great to keep this stuff organized. 

Food:
Some tips on food. For motorcycle camping, bringing enough of the right food can be a challenge. With the trailer, I carry a cooler mounted on the tongue. But, without the trailer, a soft cooler has worked well for us. All of your food can be kept in the soft cooler, and this can easily be bungied on the back with the sleeping bag. If you don't mind them, MRE's are an option, but I prefer fresh food, and the MRE's have gotten expensive.

• We freeze enough meat for as many days as we can provision for. This way, it helps keep the cooler cold, and lasts longer.
  
• We always carry the instant Jello pudding mix for something sweet, and powdered milk, just in case we can not get fresh.
• If you do buy milk, get it in pint containers. You will not likely use more than that before it becomes risky to drink, and milk is difficult to carry on the bike. Few things are more unpleasant than spilled milk in your cooler.
• Fresh vegetables are easy to get locally when you get to the area where you will be camping. These can store in the cooler as well, in a zip lock.
• I also carry a few cans of greens stuffed in my bags to fill space, and a P 38 to open them. 
• A couple of potato's stuffed in the cooler will also come in handy.
• Bring aluminum foil. A baked potato can be done in the fire at night, and is a versatile food. You can cut it up in the morning for home fries, you can keep it to gnaw on for lunch. You can even throw it in your sleeping bag at night for a warmer.
  

Clothes (Think Layers):

• I would suggest bringing a set of sandals for wearing in public showers, or if you end up wading in rivers.

Tools:

• I always carry plenty of zip ties. I have a million uses for them.
• I also always carry vice grips. I rode an old BSA chopper all the way from the Grand Canyon back to Phoenix using vice grips for a shifter.

Other items:

• Bring a flashlight, and spare batteries. Try to  keep everything that takes batteries consistent. If your flashlight takes AA batteries, ideally, your camera, and portable radio should also take AA batteries. Rechargable items are not ideal, unless you plan on using only campsites with electrical hook ups.

• Air mattresses are nice, but I have never had any luck with them. An exercise mat takes more room, but is very comfortable.
• I would recommend a collapsible water container. A water bottle is fine for drinking, but it gets old lugging pots and pans back and forth to the closest water spigot.  Bring the water to you.