Hard starting when cold, runs rough at idle and any steady speed.

Your carburetors need to be cleaned. The pilot jets are at least partially plugged.

If you are comfortable doing this yourself, you need to remove the seats, fuel tank, and air induction system before you will be able to get the carbs out. Be carefull when removing the fuel tank, there is a wire harness that will need to be un plugged from it to remove it. The wire harness plug runs under the plastic tray under the seat. There are 3 plastic rivits that will need to be removed to get to the plug. The carbs come out as a pair, and can be tough to get back in the boots.

You need to remove the float bowls, remove the jets, and blow carb cleaner and compressed air through them all. The pilot jets are most likely the only culprit, but you might as well clean everything if your going to all the trouble. You should also blow carb cleaner and compressed air through all of the other passages while your at it. Make sure that you can see through the jets and there is no debris left in them. Make sure to clean the floats, needle valves, and float bowls as well.

Then re-assemble

This happens when the bike sits for long periods. The fuel we get now days has a very short shelf life before it goes bad. Fuel oxydizes over time, and it happens even faster in a small amount that is vented which is exactly as it is when its in the carburetors of a motorcycle. When fuel oxydizes and evaporates, it leaves a gummy mess behind. The pilot jets are the smallest passages that sit in the fuel, so they naturally plug first.

You can prevent this by keeping fuel stabilizer in your fuel when ever the bike will be sitting for long periods of time. Myself personally, when I store one for the winter, I like to leave the carbs empty.