I am in the process of parting out my second Schwinn Exerciser (viewtopic.php?f=2&t=54524) There are some cool parts to use off of these and they are usually in great shape since they have typically been kept indoors. One cool part is the S2 rim. It is very heavy because of the solid core tire. The person that bought my first part out rim planned on using it for a friction drive, so he needed the hard tire. But I believe most people like these wheels because they can get a very nice 20" S2 rim for their StingRay projects. Shipping this thing is a beast because of the weight. I had one RRBer request that I remove the tire to cut down on the shipping. I wasn't willing to do this because I was afraid I would damage the rim. The person that ended up buying it told me I could remove the tire if I wanted. After thinking it over, I came up with a safe way to remove it. I clamped the tire into a workmate table and adjusted the depth of my circular saw so it would only go about 3/4 of the way into the tire. I made a few slices. Then I took our a sharp chisel and a strong utility knife and worked one of the cuts all the way down into the rim wall. Once it was cut, I just peeled the tire off. Turns out it isn't solid core. Here are some photos of the tire. I forgot to take any after shots of the rim and it is already packaged up for shipping.