Yes they come lubed pretty well, but like JEB said, use the good waterproof stuff and you will be happier. As for the tank swap, no problem. I put the tank/seat/shrouds from my '01 125 sx on my '00 200 when I had it, with no problems. It still didn't handle like the 125, but it was much easier to move around on. I don't know if the tank will work with the 200's seat though. If you are going to buy a 125 sx gas tank for your 200, why not buy the 11 liter version (stock is 8 liter). It's the same shape as the regular gas tank except down at the petcock area. They enlarge it like the offroad tanks in that area as well as adding capacity under the seat and behind the radiators. The bottom line is that you can't feel the difference from the saddle and I believe it's the same price as the 8 liter tank.