I haven't taken a trip of that length.....yet. Most I've made is a couple of 600 mile trips. From what I've read, the belt should be of no concern. Aside from the standard pre-trip oil change, inspection, etc.; the must haves, in my opinion, are:
Spare fuses. 20amp
1 qt of your favorite oil. The bike's been known to use some on long rides.
A spare container of fuel http://media.rei.com/media" alt="" title="" border="0" />
These seem to be favored by the ADV rider group. REI, and Cabella's carries them. I did run out of gas on one of those long trips due to miscalculating headwinds. 20 oz of fuel can make the difference between a long walk and a short refuel to get you going again. It may only weigh short of 400lbs wet; but it really sucks to have to push that load.
Count on rain, no matter the forcast. Count on cold if going to higher elevations. Bring appropriate gear.
Have some water and a snack. DON'T count on making it to your next stop for groceries. If, heaven forbid, you do get stranded; you'll want something to munch on. A bottle of water and a granola bar don't take up much space.
Basic tools. Not the Suzuki crap that comes with the bike. Get some real tools, and practise doing some of the things that might happen on the road WITH THOSE TOOLS. It sucks to get out in the middle of nowhere, need to take the seat off to get to the spark plug and realize that the wrench that fit in the garage, won't actually budge the bolt on the side of the road.
A spare spark plug.
A flashlight.
Duct tape.
Zip ties.
Electrical tape.
One of those thermal blankets that looks like a big piece of aluminum foil. If you get stranded at night it'll keep you warm. Makes a decent ground cover too.
Controversial; but I do take a can of Fix-a-Flat, as well as a Co2 inflator. If it's just a puncture, you can use the Fix-a-Flat to get it to hold pressure, roll it at low speeds for a couple of miles to get the goo to set, then reinflate the tire with the Co2. Won't work on major blow outs or the like; but it might be the difference between getting you to the next town, and a new tire and tube, and calling for a tow.
Fully charged cell phone. I use a Tracphone for travel. Cheap, not a huge loss if lost or stolen, and I've never had a problem with signal anywhere.
Leatherman type tool.
Throttle Rocker. I have the left and right hand. Your hands will thank you.
A good pocket knife. Not a little "apple peeler", but a good solid folder, with a legal blade.
That's about all I can think of at the moment. Peruse some of the long distance MC travel sites, like ADV rider, for additional tips. Mount up, have fun, and take some pics!
Have a safe trip.

Just got back from 1300 miles in 5 riding days.  You will find that your gluteous maximus (buttocks) will not appreciate more than 400 - 500 or so miles per day.  It helps some to have a VistaCruise (throttle lock) and a Throttle Rocker.  Also to change positions:  regular position to semi-recline position (with highway pegs) to crotch rocket position (feet on passenger pegs, leaning forward over the fuel tank).  A stuffed luggage bag on the passenger seat gives your back something to rest on as needed.

I've never run out of gas, as my habit is to stop every 100 miles for fuel and stretch.  But I have hit some deserted stretches of highway which made me sweat, worried that I would run out of gas at 125+ miles between fill-ups.  Otherwise I agree with Jay.

Get a tube of 5 minute epoxy and toss it in your tool roll. It will seal up most any small cracks in the engine casings. Real cheap insurance in case of a hit from a rock or a spill. Take some aluminum foil along and you can make a epoxy, aluminum foil bandaid.

I like the epoxy idea!!!  I also carry a small roll of duct tape & a roll of tie wire, just incase something needs to be reattached till you get home.

I've got tons of miles between fill-ups due to my oversized main and my extra tour tank. I tend to tough it out and go three hours or so at a stretch before getting off for a walk about. I've done some 650 mile days in a row and a few 2,200 mile one way trips (do the math for round trips) and swear by the V-Star saddle seat I have on the bike. I picked up a full saddle gel seat pad which didn't do as much as I had wanted, but I didn't get it until one of those long trips was almost 2/3 done. I'm waiting to try it for an entire trip starting from the git-go. I also tried one of those bead seats and it was okay for a while. Turns out it's  much better between your back and a stuffed bag on the back seat. It lets a lot of air get around to help keep you dry. And you get a bit of a massage in the deal.

Move around on the seat-cheek to cheek,
       slide forward, slide back
Mount yourself a cup holder of some sort
       on the right side and drink plenty of
       liquids. I swear by Gatoraide. My trips
       seem to be in 100 degrees in July/August
       down to FL and back
Put some cheap floorboards on there with some
       thick rubber pads to absorb the vibration
Get one of the full sized windscreens. National
       Cycle has a nice one in my opinion despite
       their cheap plastic bar clamps
Carry extra oil and a filter and use synthetic for
       the heat from constant running
Take a ton of pictures with  your digital camera

There's my three fifty's worth of advice.

Jack

Skid Mark wrote on 04/21/09 at 13:32:46:


Duct tape and wire = Harley rebuild kit.

Phelonius

Phelonoius:

I'll have to remember that next time I'm around any Harleys