Have a really close look with a strong light at the right side of the center cases. Right above the swingarm mount there is one of the screws that holds the center cases together, look very carefully in this area for a crack. If you think you see one, you probably do. These motors were known for breaking in this area. Huaberg has replaced the cases twice on my 01 501, they have been good at taking care of me, but, it does take a while to get it done. What with the required paper trail and all.
Keeping in mind that I still own my 01 501 and have done all the upgrades mentioned in this thread, and have every intention of keeping it....... Consider the fact that you would pay $2600 for the initial cost, another $1100 in parts that's $3700. And you will not be able to do all the work yourself unless you have a good shop, as there is some work with a press that will be required, and you will have to machine the crank I'm pretty sure so that it will accept the double row bearing for the counter shaft. While you've got the motor apart you might as well put a rod kit in it just to be sure, and that's where you're going to need some help getting the crank set up properly to have the proper radial end play with the crank. So let's say you go with a rod kit, that's at least $300, so now you're up to $4000 just in parts. And, even if you upgrade to a 2003 level you'll still have the SEM ignition and Dellorto carb. Have a good look at the stator and see if there are any cracks forming on the stator casing, and while you're there it'll be easy to see if there is any rust on the stator pick up points, what happens is the rust continues down inside where you can't see it, and just like water that get's into a crack on a rock and freezes, it will eventually start to break apart the expoxy resin and push the windings apart. If there is heavy corrosion I would really think twice about this bike, or at least how much the guy wants for it. Another thing to check would be to look at the oil in the sight glass, is there any? Open the fill cap and have a sniff, does it smell burnt? Have a look in the radiator, and see what's going on in there.
Do you know this person who is selling you the bike? Do you know how many hours are on it? This is pretty important b/c if it has more than 70 hours you're going to need to pull the head and check the valves. Has the suspesion ever been serviced?, there were upgrades there too between 01 and 02. How was the motor taken care of? Like the fine racing machine it is, or was has it been ridden hard and put away wet on more than one occasion?
Here's a good one, how many sets of tires has it had on it? If they are the originals, you definitely have a diamond in the rough. I have seen more than one 4 or 5 year old bike with the original tires on it. These bikes just need to be flushed thoroughly, have the suspension serviced, and your in business because the bike probably doesn't have more than 10 hours on it. The rocker and other upgrades can wait for another 40 or 50 hours, at least that was my experience.
I don't mean to rain on your parade but, I got burned when I bought my first Husaberg, it was totally clapped out, and I ended up having to put about $2500 into it, parts and labor, from then on it was flawless. Don't get me wrong, these are great bikes, and they have gotten better and better since 2001. I would just hate to see you spend the money on this bike and then end up having to spend a boat load more, and not be out riding and enjoying yourself.
But consider this, any new 04 or later model Husaberg FE model has a one year warranty on it, and has all the upgrades that we have been talking about. If you can afford it, I would definitely look into the 04 that risky 1 is talking about, or contact Dan at Motoxotica as I hear he has some pretty good deals on some left over 2005's.
So, really you just have to weigh your options. If you can get the bike for $2000, and don't mind putting anther $3000 into it before you ride it to bring it up to not only current spec for that series, but, to also bring it up to a level of maintenance to where you know what the condition of everything is. Because if you just buy the bike and ride it and it scatters, it's going to be big bucks to make the repairs, or those big bucks will be too much to justify and you'll just have to part it out to try and recover some of your money. Again, don't mean to rain on your parade here, just want you to consider all the vairables. Oh, and don't be mistaken about other brands, they al break and they all cost big bucks if you scatter the motor.
