I have bought a used bike with M975 wheels. 19mm inner rim width, 26X2.0 tires. One tire was deflated and loose on the rim. I got if off the rim with just a little effort. The other inflated OK and held air for a day or so. Soapy water foamed around the rim/wheel mounting area. Today the tire is STUCK to the rim. I've been using 91% iso alcohol and letting it soak a bit several times. I still can't get the tire to separate enough from the rim to even begin to get a lever in. I have no idea what sealant was used. Any ideas to get it off?? Thanks!!!