Recntly, I decided to get a Continental Ultrasport Hometrainer and a cheap wheel in order to keep the wear and tear off of my more expensive tires. I got the wheel from Nashbar (it's a Shimano 2200 hub laced to an Alex RFP15 rim) for 30 bucks. The problem is getting the tire seated properly. When the tire is on, part of it sits in the middle of the rim, rather than the bead "hooking" where it should. In other words, the bead seat line on the outside of the tire isn't visible on a section of rim. When this has happened to with other tight tires, I just inflate the tube and the tire will "pop" into place. Not so with this one. I keep blowing the tube no matter what I try. Usually, there is a gash close to the valve stem.
I'm just about out of ideas. I've tried inflating in stages, spraying the tire with Bike Lust (silicone spray), fiddling with the rim tape, etc. No matter what, when it gets to around 90 psi, after a while the tube will start hissing away.
Any suggestions?