LazyW: I changed the front sprocket on my '08. When I took the single nut off I too had trouble getting the sprocket off. I tapped it a few times with a mallet and got a couple of slot screwdrivers behind it, twisting them to eased it forward a bit, moved the screwdrivers a few inches aroiund and repeated until I had gone all the way around, approx 6 positions. The sprocket was out approx 1/4 in or so and I was able to pull it off by hand at that point. Perhaps a spray of WD40 or liquid wrench would help also. (I used WD40). As for the swing arm, it probably never got more than the factory grease on it, in other words, none !!! EVER !!! If a mallet wont break it loose you can try turning the bolt with a wrench/breaker bar ? I know you took the nut off but I'd think that turning the bolt will help break it loose. Again, a little, or alot, of penetrating oil on the nut end, with the bike on it's side, may help. If you can get it turning, tap on the thread (nut) end while turing the other, that should get it moving. If that doesn't work I'd consider getting a new KLR.